We are focused on value-conscious travelers who pay for their own travel, and our business model is designed to deliver what our customers want: low fares and a great experience. We use low fares to address underserved markets, which helps us to increase passenger volume and load factors on the flights we operate. We also have high-density seating configurations on our aircraft and a simplified onboard product designed to lower costs. High passenger volumes and load factors help us sell more ancillary products and services, which in turn allows us to reduce the base fare we offer even further. We strive to be recognized by our customers and potential customers as the low-fare leader in the markets we serve.

Below is a route map of our current network, which includes seasonal routes and routes announced as of January 21, 201929, 2020 for which service has not yet started:

The airline industry is highly competitive. The principal competitive factors in the airline industry are fare pricing, total price, flight schedules, aircraft type, passenger amenities, number of routes served from a city, customer service, safety record and reputation, code-sharing relationships and frequent flyer programs and redemption opportunities. Our competitors and potential competitors include traditional network airlines, other low-cost carriers and ULCCs, and regional airlines. We

As of December 31, 2018,2019, our top two largest network overlaps are with Southwest Airlines and American Airlines at approximately 59%62% and 48%44% of our markets, respectively. Our principal competitors on domestic routes are Southwest Airlines, American Airlines, Delta Air Lines, American Airlines and United Airlines. Our principal competitors to our markets in the Caribbean and Latin

The airline industry is particularly susceptible to price discounting because, once a flight is scheduled, airlines incur only nominal incremental costs to provide service to passengers occupying otherwise unsold seats. The expenses of a scheduled aircraft flight do not vary significantly with the number of passengers carried and, as a result, a relatively small change in the number of passengers or in pricing could have a disproportionate effect on an airline’s operating and financial results. Price competition occurs on a market-by-market basis through price discounts, changes in pricing structures, fare matching, target promotions and frequent flyer initiatives. Airlines typically use discount fares and other promotions to stimulate traffic during normally slower travel periods to generate cash flow and to maximize TRASM. The prevalence of discount fares can be particularly acute when a competitor has excess capacity that it is unable to fill at higher rates. A key element to our competitive strategy is to maintain very low unit costs in order to permit us to compete successfully in price-sensitive markets.

We are committed to taking care of our customers. We believe focusing on customer service in every aspect of our operations, including personnel, flight equipment, in-flight and ancillary amenities, on-time performance, flight completion ratios, and baggage handling, will strengthen customer loyalty and attract new customers. We proactively aim to improve our operations to ensure further improvement in customer service.

Our online booking process allows our customers to see all available options and their prices prior to purchasing a ticket. We maintain a campaign that illustrates our total prices are lower, on average, than those of our competitors, even when options are included.

We fly only Airbus A320 family aircraft, which provides us significant operational and cost advantages compared to airlines that operate multiple aircraft types. By operating a single aircraft type, we avoid the incremental costs of training crews across multiple types. Flight crews are entirely interchangeable across all of our aircraft, and maintenance, spare parts inventories and other operational support remains highly simplified compared to those airlines with more complex fleets. Due to this commonality among Airbus single-aisle aircraft, we can retain the benefits of a fleet comprised of a single type of aircraft while still having the flexibility to match the capacity and range of the aircraft to the demands of each route.

On December 20, 2019, we entered into an A320 NEO Family Purchase Agreement with Airbus S.A.S. ("Airbus") for the purchase of 100 new Airbus A320neo family aircraft, with options to purchase up to 50 additional aircraft. This agreement includes a mix of Airbus A319, A320 and A321 aircraft with such aircraft scheduled for delivery through 2027. As of December 31, 2018,2019, our firm aircraft orders consisted of 50135 A320 family aircraft (2 A320ceos and 43 A320neos with Airbus, including A319neos, A320neos and an additional 5A321neos, with deliveries expected through 2027. In addition, we had 12 direct operating leases for A320neos with a third-party lessor). During the first quarter of 2018, we negotiated revisions to our A320 aircraft orderlessors, with Airbus. We originally had 14 A320neo aircraft scheduled for delivery in 2019. Pursuant to the revision, 5 of the 14 scheduled A320neo aircraft were converted to A320ceo aircraft, of which 3 were delivered in the fourth quarter of 2018 and the remaining 2 are scheduled to be delivered in 2019.deliveries expected through 2021. As of December 31, 2018,2019, spare engine orders consisted of twoone V2500 SelectTwo enginesengine with IAE and eightfour PurePower PW 1100G-JM engines with Pratt & Whitney. Aircraft areWhitney scheduled for delivery from 20192020 through 2021 and spare engines are scheduled for delivery from 2019 through 2024.2023. The firm aircraft orders provide for capacity growth as well as the flexibility to add to, or replace, the aircraft in our present fleet. We may elect to supplement these deliveries by additional acquisitions from the manufacturer or in the open market if demand conditions merit. We also may adjust or defer deliveries, or change models of aircraft in our delivery stream, from time to time, as a means to match our future capacity with anticipated demand and growth trends.

Consistent with our ULCC business model, each of our aircraft is configured with a high density seating configuration, which helps us maintain a lower unit cost and pass savings to our customers. Our high density seating configuration accommodates more passengers than those of our competitors when comparing the same type of aircraft.

We have a Federal Aviation Administration ("FAA") mandated and approved maintenance program, which is administered by our technical services department. Our maintenance technicians undergo extensive initial and ongoing training to ensure the safety of our aircraft. For the second year in a row, we have achieved the FAA's highest award for Technical Training, the Diamond Award of Excellence. This award is only achieved if 100% of technicians receive the FAA's Aircraft Maintenance Technician ("AMT") Certificate of Training.

Aircraft maintenance and repair consists of routine and non-routine maintenance, and work performed is divided into three general categories: line maintenance, heavy maintenance and component service. Line maintenance consists of routine daily and weekly scheduled maintenance checks on our aircraft, including pre-flight, daily, weekly and overnight checks, and any diagnostics and routine repairs and any unscheduled items on an as needed basis. Line maintenance events are currently serviced by in-house mechanics supplemented by contract labor and are primarily completed at airports we currently serve. Heavy airframe maintenance checks consist of a series of more complex tasks that can take from one to four weeks to accomplish and typically are required approximately every 24 to 36 months. Heavy engine maintenance is performed approximately every six years and includes a more complex scope of work. Due to our relatively small fleet size and projected fleet growth, we believe outsourcing all of our heavy maintenance activity, such as engine servicing, heavy airframe maintenance checks, major part repair and component service repairs is more economical. Outsourcing eliminates the substantial initial capital requirements inherent in heavy aircraft maintenance. We have entered into a long-term flight hour agreement for the majority of our current fleet and future deliveries with IAE and Pratt & Whitney for our engine overhaul services and with Lufthansa Technik on an hour-by-hour basis for component services. We outsource our heavy airframe maintenance to FAA-qualified maintenance providers.

Our recent maintenance expenses have been lower than what we expect to incur in the future because of the relatively young age of our aircraft fleet. Our maintenance costs are expected to increase as the scope of repairs increases with the increasing age of our fleet. As our aircraft age, scheduled scope of work and frequency of unscheduled maintenance events is likely to increase like any maturing fleet. Our aircraft utilization rate could decrease with the increase in aircraft maintenance.

In the first quarter of 2017, we opened a 126,000-square-foot maintenance hangar facility, adjacent to the airfield at the Detroit Metropolitan Wayne County Airport, which allows us to fulfill the maintenance requirements of our growing fleet and will reduce dependence on third-party facilities and contract line maintenance. Please see “-Properties-Ground Facilities.”

FAA regulations require pilots to have commercial licenses with specific ratings for the aircraft to be flown and be medically certified as physically fit to fly. FAA and medical certifications are subject to periodic renewal requirements, including recurrent training and recent flying experience. Mechanics, quality-control inspectors and dispatchers must be certificated and qualified for specific aircraft. Flight attendants must have initial and periodic competency training and qualification. Training programs are subject to approval and monitoring by the FAA. Management personnel directly involved in the supervision of flight operations, training, maintenance and aircraft inspection must also meet experience standards prescribed by FAA regulations. All safety-sensitive employees are subject to pre-employment, random and post-accident drug testing.

The Railway Labor Act, or RLA, governs our relations with labor organizations. Under the RLA, our collective bargaining agreements do not expire, but instead become amendable as of a stated date. If either party wishes to modify the terms of any such agreement, they must notify the other party in the manner agreed to by the parties. Under the RLA, after receipt of such notice, the parties must meet for direct negotiations. If no agreement is reached, either party may request the National Mediation Board, or NMB, to appoint a federal mediator. The RLA prescribes no set timetable for the direct negotiation and mediation process. It is not unusual for those processes to last for many months, and even several years. If no agreement is reached in mediation, the NMB in its discretion may declare at some time that an impasse exists. If an impasse is declared, the NMB proffers binding arbitration to the parties. Either party may decline to submit to arbitration. If arbitration is rejected by either party, a 30-day “cooling off” period commences. During that period (or after), a Presidential Emergency Board, or PEB, may be established, which examines the parties’ positions and recommends a solution. The PEB process lasts for 30 days and is followed by another “cooling off” period of 30 days. At the end of a “cooling off” period, unless an agreement is reached or action is taken by Congress, the labor organization and the airline each may resort to “self-help,” including, for the labor organization, a strike or other labor action, and for the airline, the imposition of any or all of its proposed amendments and the hiring of new employees to replace any striking workers. Congress and the President have the authority to prevent “self-help” by enacting legislation that, among other things, imposes a settlement on the parties. The table below sets forth our employee groups and status of the collective bargaining agreements.

In August 2015, our collective bargaining agreement with our pilots, represented by ALPA, became amendable. In June 2016, ALPA requested the services of the NMB to facilitate negotiations for an amended agreement and we joined ALPA in the request. In January 2018, under the guidance of the NMB assigned mediators, the parties reached a tentative agreement. In February 2018, the pilot group voted to approve the newcurrent five-year agreement. In connection with the newcurrent agreement, we incurred a one-time ratification incentive of $80.2 million, including payroll taxes, and an $8.5 million adjustment related to other contractual provisions. These amounts were recorded in special charges within operating expenses in the statement of operations for the year ended December 31, 2018. For additional information, refer to “Notes to the Financial Statements—5.4. Special Charges.”

In March 2016, under the supervision of the NMB, we reached a tentative agreement for a five-year contract with our flight attendants and in May 2016, the flight attendants voted to approve the new five-year contract. In connection with this agreement, we paid a $9.6 million ratification incentive payment to the flight attendants recorded within salaries, wages and benefits in the statements of operations. Of the total ratification incentive, $8.4 million was recorded during 2016 as the remaining $1.2 million was previously accrued in 2015.

In December 2017, PAFCA filed an application with the NMB seeking to represent ourOur dispatchers who were previously represented by the TWU.  In January 2018, the NMB determined that a representation election would be held. The voting

In July 2014, certain ramp service agents directly employed by the Companyus voted to be represented by the IAMAW. In May 2015, we entered into a five-year interim collective bargaining agreement with the IAMAW, covering material economic terms. In June 2016, we reached an agreement on the remaining terms of the collective bargaining agreement, which is amendable in June 2020.

In June 2018, we were notified by the NMB that the TWU filed an application seeking a representation election for our passenger service agents. Our passenger service agents voted to be represented by the TWU, but the representation only applies only to theour Fort Lauderdale station where we have direct employees in the passenger service classification. We began meeting with the TWU in late October 2018 to negotiate an initial collective bargaining agreement. As of December 31, 2019, we continued to negotiate with the TWU.

We focus on hiring highly productive employees and, where feasible, designing systems and processes around automation and outsourcing in order to maintain our low-cost base.

We are committed to the safety and security of our passengers and employees. We strive to comply with or exceed health and safety regulation standards. In pursuing these goals, we maintain an active aviation safety program. All of our personnel are expected to participate in the program and take an active role in the identification, reduction and elimination of hazards.

Our ongoing focus on safety relies on training our employees to proper standards and providing them with the tools and equipment they require so they can perform their job functions in a safe and efficient manner. Safety in the workplace targets several areas of our business, including: flight operations, maintenance, in-flight, dispatch and station operations. The Transportation Security Administration, or TSA, is charged with aviation security for both airlines and airports. We maintain active, open lines of communication with the TSA at all of our locations to ensure proper standards for security of our personnel, customers, equipment and facilities are exercised throughout our business.

We maintain insurance policies we believe are customary in the airline industry and as required by the Department of Transportation ("DOT"). The policies principally provide liability coverage for public and passenger injury; damage to property; loss of or damage to flight equipment; fire and extended coverage; war risk (terrorism); directors’ and officers’ liability; advertiser and media liability; cyber risk liability; fiduciary; and workers’ compensation and employer’s liability. Renewing coverage could result in a change in premium and more restrictive terms. Although we currently believe our insurance coverage is adequate, there can be no assurance that the amount of such coverage will not be changed or that we will not be forced to bear substantial losses from accidents.

We have continued our commitment to technology improvements to support our ongoing operations and initiatives. In 2016, we upgraded the Sabre Flight Operating Suite to Flight Plan Manager. During 2017, we completed the migration of critical operating and sales systems into a state-of-the-art data center facility in South Florida, implemented a new customer mobile application, deployed all new self-service kiosks, and improved the customer experience on our website.

In 2019, we began the process of upgrading our enterprise accounting software. This project was suspended in the third quarter of 2019 and we have elected to re-evaluate and pursue the optimal solution. In addition, we implemented a new website built on a more stable codebase which provides for a better user experience. In addition, we invested in improving the stability of our mobile application.

Throughout 2020, we will continue migratingto migrate critical business applications into the cloud infrastructure, allowing us to take increasing advantage of the analytics and automation functions. These improvements provide further opportunities to increase business intelligence and flexibility, improve business continuity, mitigate disaster scenarios and enhance data security. We intend to continue to invest time and resources in upgradingcyber security to protect our data, operations and improving our information systems and the security of our data.customers' privacy.

Under DOT regulations and federal law, we must be controlled by U.S. citizens. In order to qualify, at least 75% of our stock must be voted by U.S. citizens, and our president and at least two-thirds of our board of directors and senior management must be U.S. citizens.

The airline industry is heavily regulated, especially by the federal government. Two of the primary regulatory authorities overseeing air transportation in the United States are the DOT and the FAA. The DOT has jurisdiction over economic and consumer issues affecting air transportation, such as competition, route authorizations, advertising and sales practices, baggage liability and disabled passenger transportation, reporting of mishandled bags, tarmac delays and responding to customer complaints among other areas. In October 2018, following the enactment of the FAA Reauthorization Act of 2018, the DOT enacted an Enforcement Notice addressing the obligations of U.S. carriers to report certain data for mishandled baggage, wheelchairs, and scooters, and established a new compliance date of December 6, 2018. In May 2016,August 2019, the DOT issued an Advance Notice of Proposed Rulemaking to seek comment on amending its Air Carrier Access Act regarding transportation of service animals, as well as an Interima Final Statement of Enforcement Priorities Regarding Service Animals, to highlight its intended enforcement focus.focus pending issuance of a new rule. In January 2020, the DOT issued a Notice

The DOT has authority to issue certificates of public convenience and necessity required for airlines to provide air transportation. We hold a DOT certificate of public convenience and necessity authorizing us to engage in scheduled air transportation of passengers, property and mail within the United States, its territories and possessions and between the United States and all countries that maintain a liberal aviation trade relationship with the United States (known as “open skies” countries). We also hold DOT certificates to engage in air transportation to certain other countries with more restrictive aviation policies.

The FAA is responsible for regulating and overseeing matters relating to air carrier flight operations, including airline operating certificates, aircraft certification and maintenance and other matters affecting air safety.safety, including rest periods and work hours for all airlines certificated under Part 121 of the Federal Aviation Regulations. The FAA requires each commercial airline to obtain and hold an FAA air carrier certificate. This certificate, in combination with operations specifications issued to the airline by the FAA, authorizes the airline to operate at specific airports using aircraft approved by the FAA. As of December 31, 2018,2019, we had FAA airworthiness certificates for all of our aircraft, we had obtained the necessary FAA authority to fly to all of the cities we currently serve, and all of our aircraft had been certified for overwater operations. In 2014, the FAA issued its final regulations governing rest periods and work hours for all airlines certificated under Part 121 of the Federal Aviation Regulations. The rule, known as FAR 117 which became effective on January 4, 2014, impacts the required amount and timing of rest periods for pilots between work assignments, and modifies duty and rest requirements based on the time of day, number of scheduled segments, flight types, time zones and other factors. FAR 117 resulted in increased pilot costs as we were required to hire more pilots in order to comply with the regulations. Any new or revised operational regulations in the future could result in further increased costs. We believe we hold all necessary operating and airworthiness authorizations, certificates and licenses and are operating in compliance with applicable DOT and FAA regulations, interpretations and policies.

All international service is subject to the regulatory requirements of the foreign government involved. We currently offer international service to Aruba, Colombia, Costa Rica, Dominican Republic, Ecuador, El Salvador, Guatemala, Haiti, Honduras, Jamaica, Mexico, Nicaragua, Panama, Peru and St. Maarten, as well as Puerto Rico and the U.S. Virgin Islands. If we decide to increase our routes to additional international destinations, we will be required to obtain necessary authority from the DOT and the applicable foreign government. We are also required to comply with overfly regulations in countries that lay along our routes but which we do not serve.

International service is also subject to Customs and Border Protection, or CBP, immigration and agriculture requirements and the requirements of equivalent foreign governmental agencies. Like other airlines flying international routes, from time to time we may be subject to civil fines and penalties imposed by CBP if unmanifested or illegal cargo, such as illegal narcotics, is found on our aircraft. These fines and penalties, which in the case of narcotics are based upon the retail value of the seizure, may be substantial. We have implemented a comprehensive security program at our airports to reduce the risk of illegal cargo being placed on our aircraft, and we seek to cooperate actively with CBP and other U.S. and foreign law enforcement agencies in investigating incidents or attempts to introduce illegal cargo.

We are subject to various federal, state and local laws and regulations relating to the protection of the environment and affecting matters such as aircraft engine emissions, aircraft noise emissions and the discharge or disposal of materials and chemicals, which laws and regulations are administered by numerous state and federal agencies. The Environmental Protection Agency, or EPA, regulates operations, including air carrier operations, which affect the quality of air in the United States. We

Federal law recognizes the right of airport operators with special noise problems to implement local noise abatement procedures so long as those procedures do not interfere unreasonably with interstate and foreign commerce and the national air transportation system. These restrictions can include limiting nighttime operations, directing specific aircraft operational procedures during takeoff and initial climb, and limiting the overall number of flights at an airport.

We are subject to certain provisions of the Communications Act of 1934, as amended, and are required to obtain an aeronautical radio license from the Federal Communications Commission, or FCC. To the extent we are subject to FCC requirements, we will take all necessary steps to comply with those requirements. We are also subject to state and local laws and regulations at locations where we operate and the regulations of various local authorities that operate the airports we serve.

The U.S. and foreign governments may consider and adopt new laws, regulations, interpretations and policies regarding a wide variety of matters that could directly or indirectly affect our results of operations. We cannot predict what laws, regulations, interpretations and policies might be considered in the future, nor can we judge what impact, if any, the implementation of any of these proposals or changes might have on our business.

We face significant competition with respect to routes, fares and services. Within the airline industry, we compete with traditional network airlines, other low-cost airlines and regional airlines on many of our routes. Competition in most of the destinations we presently serve is intense, sometimes due to the large number of carriers in those markets. Furthermore, other airlines may begin service or increase existing service on routes where we currently face little competition. Most of our competitors are larger than us and have significantly greater financial and other resources than we do.

The airline industry is particularly susceptible to price discounting because once a flight is scheduled, airlines incur only nominal additional costs to provide service to passengers occupying otherwise unsold seats. Increased fare or other price competition has, and may continue to, adversely affect our revenue generation. Moreover, many other airlines have begun to unbundle services by charging separately for services such as baggage and advance seat selection. This unbundling and other cost reducing measures could enable competitor airlines to reduce fares on routes that we serve. Beginning in 2015, and continuing through 2018, the2019, more widespread availability of low priced fares, including from legacy network carriers, coupled with an increase in domestic capacity led to dramatic changes in pricing behavior in many U.S. markets. Many domestic carriers began matching lower cost airline pricing, either with limited or unlimited inventory.

Airlines increase or decrease capacity in markets based on perceived profitability, market share objectives, competitive considerations and other reasons. Decisions by our competitors that increase overall industry capacity, or capacity dedicated to a particular domestic or foreign region, market or route, could have a material adverse impact on our business. If a traditional network airline were to successfully develop a low-cost structure, compete with us on price or if we were to experience increased competition from other low-cost carriers, our business could be materially adversely affected.

Our growth and the success of our ULCC business model could stimulate competition in our markets through our competitors’ development of their own ULCC strategies, new pricing policies designed to compete with ULCCs or new market entrants. Any such competitor may have greater financial resources and access to less expensive sources of capital than we do, which could enable them to operate their business with a lower cost structure, or enable them to operate with lower-marginal revenues without substantial adverse effects, than we can. If these competitors adopt and successfully execute a ULCC business model, we could be materially adversely affected. In 2015, Delta Air Lines began to market and sell a "Basic Economy" fareproduct which was designed in part to provide its customers with a low base fare similar to Spirit. In 2017, American Airlines and United Airlines announced their own "Basic Economy" fare,product, and other airlines like Alaska Airlines and beginning in late 2019, JetBlue, have also followed suit.

The extremely competitive nature of the airline industry could prevent us from attaining the level of passenger traffic or maintaining the level of fares or revenues related to ancillary services required to sustain profitable operations in new and existing markets and could impede our growth strategy, which could harm our operating results. Due to our relatively small size, we are susceptible to a fare war or other competitive activities in one or more of the markets we serve, which could have a material adverse effect on our business, results of operations and financial condition.

Our low-cost structure is one of our primary competitive advantages. However, we have limited control over many of our costs. For example, we have limited control over the price and availability of aircraft fuel, aviation insurance, airport costs and related infrastructure taxes, the cost of meeting changing regulatory requirements and our cost to access capital or financing. In addition, the compensation and benefit costs applicable to a significant portion of our employees are established by the terms of our collective bargaining agreements. We cannot guarantee we will be able to maintain a cost advantage over our competitors. If our cost structure increases and we are no longer able to maintain a sufficient cost advantage over our competitors, it could have a material adverse effect on our business, results of operations and financial condition.

Aircraft fuel prices have been subject to high volatility, fluctuating substantially over the past several years. For example, our fuel prices spiked at a high of $3.32 per gallon, in the second quarter of 2012, fell as low as $1.22 per gallon in the first quarter of 2016 and remained at over $2.00 per gallon throughout 2018.2019. We cannot predict the future availability, price volatility or cost of aircraft fuel. Due to the large proportion of aircraft fuel costs in our total operating cost base, even a relatively small increase or decrease in the price of aircraft fuel can have a significant negative impact on our operating costs or revenues and on our business, results of operations and financial condition.

The International Maritime Organization ("IMO") has set January 1, 2020 as the implementation date for ships to comply with its new low sulfurlow-sulfur fuel oil requirements. It is uncertain how the availability and price of jet fuel around the world will be affected by the implementation of the IMO 2020 Regulations. Increased costs and/or decreased supply of jet fuel may be material and could adversely affect the Company’s results of our operations and financial condition.

From time to time, we may enter into fuel derivative contracts in order to mitigate the risk to our business from future volatility in fuel prices. Our derivatives may generally consist of United States Gulf Coast jet fuel swaps ("jet fuel swaps") and

During 2019, 2018 2017 and 2016,2017, we generated non-ticket revenues of $1,943.7 million, $1,618.9 million $1,280.2 million and $1,121.9$1,280.2 million, respectively. Our non-ticket revenues are generated from charges for, among other things, baggage, bookings through certain of our distribution channels, advance seat selection, itinerary changes and loyalty programs. The DOT has rules governing many facets of the airline-consumer relationship, including, for instance, price advertising, tarmac delays, bumping of passengers from flights, ticket refunds and the carriage of disabled passengers. If we are not able to remain in compliance with these rules, the DOT may subject us to fines or other enforcement action, including requirements to modify our passenger reservations system, which could have a material adverse effect on our business. The U.S. Congress and Federal administrative agencies have investigated the increasingly common airline industry practice of unbundling the pricing of certain products and services. If new taxes are imposed on non-ticket revenues, or if other laws or regulations are adopted that make unbundling of airline products and services impermissible, or more cumbersome or expensive, our business, results of operations and financial condition could be harmed. Congressional and other government scrutiny may also change industry practice or public willingness to pay for ancillary services. See also “—We are subject to extensive regulation by the Federal Aviation Administration, the Department of TransportationFAA, DOT, TSA and other U.S. and foreign governmental agencies, compliance with which could cause us to incur increased costs and adversely affect our business and financial results.”

Our business and the airline industry in general are affected by many changing economic conditions beyond our control, including, among others:

These factors can adversely affect, and from time to time have adversely affected, our results of operations, our ability to obtain financing on acceptable terms and our liquidity. Unfavorable general economic conditions, such as higher unemployment rates, a constrained credit market, housing-related pressures and increased focus on reducing business operating costs can reduce spending for price-sensitive leisure and business travel. For many travelers, in particular the price-sensitive travelers we serve, air transportation is a discretionary purchase that they may reduce or eliminate from their spending in difficult economic times. The overall decrease in demand for air transportation in the United States in 2008 and 2009 resulting from record high fuel prices and the economic recession required us to take significant steps to reduce our capacity, which reduced our revenues. Unfavorable economic conditions could also affect our ability to raise prices to counteract the effect of

The terrorist attacks of September 11, 2001 and their aftermath negatively affected the airline industry. The primary effects experienced by the airline industry included:

Since September 11, 2001, the Department of Homeland Security and the TSA have implemented numerous security measures that restrict airline operations and increase costs, and are likely to implement additional measures in the future. For example, following the widely publicized attempt of an alleged terrorist to detonate plastic explosives hidden underneath his clothes on a Northwest Airlines flight on Christmas Day in 2009, passengers became subject to enhanced random screening, which included pat-downs, explosive detection testing and body scans. Enhanced passenger screening, increased regulation governing carry-on baggage and other similar restrictions on passenger travel may further increase passenger inconvenience and reduce the demand for air travel. In addition, increased or enhanced security measures have tended to result in higher governmental fees imposed on airlines, resulting in higher operating costs for airlines, which we may not be able to pass on to consumers in the form of higher prices. Any future terrorist attacks or attempted attacks, even if not made directly on the airline industry, or the fear of such attacks or other hostilities (including elevated national threat warnings or selective cancellation or redirection of flights due to terror threats) would likely have a material adverse effect on our business, results of operations and financial condition and on the airline industry in general.

Like other airlines, our business is affected by factors beyond our control, including air traffic congestion at airports, air traffic control inefficiencies, major construction or improvements at airports at which we operate, adverse weather conditions, increased security measures, new travel related taxes, the outbreak of disease, new regulations or policies from the presidential administration and Congress. Factors that cause flight delays frustrate passengers and increase costs, which in turn could adversely affect profitability. The federal government currently controls all U.S. airspace, and airlines are completely dependent on the FAA to operate that airspace in a safe, efficient and affordable manner. The air traffic control system, which is operated by the FAA, faces challenges in managing the growing demand for U.S. air travel. U.S. and foreign air-traffic controllers often rely on outdated technologies that routinely overwhelm the system and compel airlines to fly inefficient, indirect routes resulting in delays. A significant portion of our operations is concentrated in markets such as South Florida, the Caribbean, Latin America and the Northeast and Northernnorthern Midwest regions of the United States, which are particularly vulnerable to weather, airport traffic constraints and other delays. Adverse weather conditions and natural disasters, such as hurricanes affecting southern Florida and the Caribbean (such as Hurricanes Irma and Maria in September 2017)2017 and Hurricane Dorian in August 2019) as well as southern Texas (such as Hurricane Harvey in August 2017), winter snowstorms or earthquakes (such as the September 2017 earthquakes in Mexico City, Mexico)Mexico and the December 2019 and January 2020 earthquakes in Puerto Rico) can cause flight cancellations, significant delays and certain facility disruptions. For example, during 2017, the timing and location of Hurricanes Irma and Maria produced a domino effect on our operations resulting in approximately 1,400 flight cancellations and numerous flight delays, which resulted in an adverse effect on our results of operations. Cancellations or delays due to adverse weather conditions or natural disasters, air traffic control problems or inefficiencies, breaches in security or other factors may affect us to a greater degree than other, larger airlines that may be able to recover more quickly from these events, and therefore could harm our business, results of operations and financial condition to a greater degree than other air carriers. Because of our high utilization, point-to-point network, operational disruptions can have a disproportionate impact on our ability to recover. In addition, many airlines reaccommodate their disrupted passengers on other airlines at prearranged rates under flight interruption manifest agreements. We have been unsuccessful in procuring any of these agreements with our

We generate a relatively small but growing portion of our revenue from commissions, revenue share and other fees paid to us by third-party merchants for customer click-throughs, distribution of third-party promotional materials and referrals arising from products and services of the third-party merchants that we offer to our customers on our website. Some of these third-party referral-based offers are for memberships in discount programs or similar promotions made to customers who have purchased products from us, and for which we receive a payment from the third-party merchants for every customer that accepts the promotion. Certain of these third-party membership discount programs have been the subject of consumer complaints, litigation and regulatory actions alleging that the enrollment and billing practices involved in the programs violate various consumer protection laws or are otherwise deceptive. Any private or governmental claim or action that may be brought against us in the future relating to these third-party membership programs could result in our being obligated to pay damages or incurring legal fees in defending claims. These damages and fees could be disproportionate to the revenues we generate through these relationships. In addition, customer dissatisfaction or a significant reduction in or termination of the third-party membership discount offers on our website as a result of these claims could have a negative impact on our brand, and have a material adverse effect on our business, results of operations and financial condition.

In addition to airline competition from traditional network airlines, other low-cost airlines and regional airlines, we also face competition from air travel substitutes. On our domestic routes, we face competition from some other transportation alternatives, such as bus, train or automobile. In addition, technology advancements may limit the demand for air travel. For example, video teleconferencing and other methods of electronic communication may reduce the need for in-person communication and add a new dimension of competition to the industry as travelers seek lower-cost substitutes for air travel. If we are unable to adjust rapidly in the event the basis of competition in our markets changes, it could have a material adverse effect on our business, results of operations and financial condition.

Our business is labor intensive, with labor costs representing approximately 24.2%26.0%, 23.4%24.2% and 25.2%23.4% of our total operating costs for 2019, 2018 2017 and 2016,2017, respectively. As of December 31, 2018,2019, approximately 80%81% of our workforce was represented by labor unions. We cannot assure that our labor costs going forward will remain competitive because in the future our labor agreements may be amended or become amendable and new agreements could have terms with higher labor costs; one or more of our competitors may significantly reduce their labor costs, thereby reducing or eliminating our comparative advantages as to one or more of such competitors; or our labor costs may increase in connection with our growth. We may also become subject to additional collective bargaining agreements in the future as non-unionized workers may unionize.

Relations between air carriers and labor unions in the United States are governed by the RLA. Under the RLA, collective bargaining agreements generally contain “amendable dates” rather than expiration dates, and the RLA requires that a carrier maintain the existing terms and conditions of employment following the amendable date through a multi-stage and usually lengthy series of bargaining processes overseen by the NMB. This process continues until either the parties have reached agreement on a new collective bargaining agreement, or the parties have been released to “self-help” by the NMB. In most circumstances, the RLA prohibits strikes; however, after release by the NMB, carriers and unions are free to engage in self-help measures such as lockouts and strikes.

During 2017, we experienced operational disruption from pilot-related work action which adversely impacted our results. We obtained a temporary restraining order to enjoin further illegal labor action. In January 2018, under the guidance of the NMB assigned mediators, the parties reached a tentative agreement. In February 2018,

In March 2016, under the supervision of the NMB, we reached a tentative agreement for a five-year contract with our flight attendants. In May 2016, we entered into a five-year agreement with our flight attendants, which becomes amendable May 2021.

In December 2017, PAFCA filed an application with the NMB seeking to represent ourOur dispatchers who were previously represented by the TWU. In January 2018, the NMB determined that a representation election would be held. The voting period for the representation election took place through February 20, 2018 and the dispatchers elected to beare represented by the PAFCA. In June 2018, the Companywe commenced negotiations with PAFCA for an amended agreement with itsour dispatchers. In October 2018, PAFCA and the Company reached a tentative agreement for a new five-year agreement, which was ratified by the PAFCA members in October 2018. The terms of the new agreement are currently in effect.

In July 2014, certain ramp service agents directly employed by us voted to be represented by the IAMAW. In May 2015, we entered into a five-year interim collective bargaining agreement with the IAMAW, including material economic terms. In June 2016, we reached an agreement on the remaining terms of the collective bargaining agreement with the IAMAW, which is amendable in June 2020.

In June 2018, the NMB notified the Company that the TWU filed an application seeking a representation election for the Company's passenger service agents. The NMB determined that a representation election would be held and the voting period for the election took place through September 4, 2018. The Company'sour passenger service agents voted to be represented by the TWU, but the representation applies only to the Company'sour Fort Lauderdale station where the Company haswe have direct employees in the passenger service classification. The Company andWe began meeting with the TWU began meeting in late October 2018 to negotiate an initial collective bargaining agreement. As of December 31, 2019, we continued to negotiate with the TWU.

If we are unable to reach agreement with any of our unionized work groups in current or future negotiations regarding the terms of their CBAs, we may be subject to work interruptions or stoppages, such as the strike by our pilots in June 2010.2010 and the operational disruption from pilot-related work action experienced in 2017. A strike or other significant labor dispute with our unionized employees is likely to adversely affect our ability to conduct business. Any agreement we do reach could increase our labor and related expenses.

The Patient Protection and Affordable Care Act was enacted in 2010. Under the current administration, this law may be repealed in its entirety or certain aspects may be changed or replaced. If the law is repealed or significantly modified or if new healthcare legislation is passed, such action could significantly increase cost of the healthcare benefits provided to our U.S. employees. In addition, the failure to comply materially with such existing and new laws, rules and regulations could adversely affect our business, results of operations and financial conditions.

The airline business is capital intensive and, as a result, many airline companies are highly leveraged. As of December 31, 2018,2019, our 128145 aircraft fleet consisted of 4652 aircraft financed under operating leases, 602 aircraft financed under finance leases, 64 aircraft financed under debt arrangements, and 2227 aircraft purchased off lease and currently unencumbered. In 20182019 and 2017,2018, we paid the lessors rent of $214.0$181.0 million and $220.9$214.0 million, respectively. In connection with our aircraft and engines, in 2019, we received maintenance deposits, net of payments, of $22.5 million and in 2018, we received maintenance deposits, net of payments, of $14.0 million and in 2017, we paid maintenance deposits, net of reimbursements, of $37.9 million. As of December 31, 2018,2019, we had future aircraft and spare engine operating lease obligations of approximately $1.2$1.8 billion. In 20182019 and 2017,2018, we made scheduled principal payments of $137.3$246.8 million and $102.3$137.3 million on our outstanding debt obligations, respectively. As of December 31, 2018,2019, we had future principal debt obligations of $2.2 billion, of which $171.4$222.1 million is due in 2019.2020. In addition, we have significant obligations for aircraft and spare engines that we have ordered from Airbus, International Aero Engines AG, or IAE, and Pratt & Whitney for delivery over the next several years. Our ability to pay the fixed costs associated with our contractual obligations will depend on our operating performance, cash flow and our ability to secure adequate financing, which will in turn depend on, among other things, the success of our current business strategy, fuel price volatility, weakening or improvement in the U.S. economy, as well as general economic and political conditions and other factors that are beyond our control. The amount of our aircraft related fixed obligations and related need to obtain financing could have a material adverse effect on our business, results of operations and financial condition and could:

A failure to pay our operating lease, debt and other fixed cost obligations or a breach of our contractual obligations could result in a variety of adverse consequences, including the exercise of remedies by our creditors and lessors. In such a situation, it is unlikely that we would be able to cure our breach, fulfill our obligations, make required lease or debt payments or otherwise cover our fixed costs, which would have a material adverse effect on our business, results of operations and financial condition.

As of December 31, 2018,2019, we had access to lines of credit from our physical fuel delivery and derivative counterparties and our purchase credit card issuer aggregating $75.1 million and an unsecured standby letter of credit facility of $35.0 million. In addition, during the fourth quarter of 2018, we entered intohave a revolving credit facility for up to $160 million on which we had drawn $135.3$160.0 million as of December 31, 2018.2019. For additional information, refer to "Notes to the Financial Statements—13,13. Debt and Other Obligations." These credit facilities are not adequate to finance our operations, and we will continue to be dependent on our operating cash flows and cash balances to fund our operations and to make scheduled payments on our aircraft related fixed obligations. In addition, our credit card processors are entitled to withhold receipts from customer purchases from us, under certain circumstances. Although our credit card processors currently do not have a right to hold back credit card receipts to cover repayment to customers, if we fail to maintain certain liquidity and other financial covenants, their rights to holdback would be reinstated, which would result in a reduction of unrestricted cash that could be material. In addition, we are required by some of our aircraft lessors to fund reserves in cash in advance for scheduled maintenance, and a portion of our cash is therefore unavailable until after we have completed the scheduled maintenance in accordance with the terms of the operating leases. Based on the age of our fleet and our growth strategy, these maintenance deposits will increase over the next few years before we receive any significant reimbursement for completed maintenance. If we fail to generate sufficient funds from operations to meet our operating cash requirements or do not obtain a line of credit, other borrowing facility or equity financing, we could default on our operating lease and fixed obligations. Our inability to meet our obligations as they become due would have a material adverse effect on our business, results of operations and financial condition.

The general worldwide economy has in the past experienced downturns due to the effects of the European debt crisis, unfavorable U.S. economic conditions and slowing growth in certain Asian economies, including general credit market crises, collateral effects on the finance and banking industries, energy price volatility, concerns about inflation, slower economic activity, decreased consumer confidence, reduced corporate profits and capital spending, adverse business conditions, geopolitical conflict, pandemic risks, government constraints on international trade and liquidity concerns. The airline industry is particularly sensitive to changes in economic conditions, which affect customer travel patterns and related revenues.  A weak economy could reduce our bookings, and a reduction in discretionary spending could also decrease amounts our customers are willing to pay.  Unfavorable economic conditions can also impact the ability of airlines to raise fares to help offset increased fuel, labor and other costs. We cannot accurately predict the effect or duration of any economic slowdown or the timing or strength of a subsequent economic recovery.

In addition, we have significant obligations for aircraft and spare engines that we have ordered from Airbus, IAE and Pratt & Whitney over the next several years, and we will need to finance these purchases. We may not have sufficient liquidity or creditworthiness to fund the purchase of aircraft and engines, including payment of PDPs, or for other working capital. Factors that affect our ability to raise financing or access the capital markets include market conditions in the airline industry,

From time to time, we may enter into fuel derivative contracts in order to mitigate the risk to our business from future volatility in fuel prices, refining risk between the price of crude oil and the price of refined jet fuel, and to manage the risk of increasing fuel prices. As of December 31, 2018,2019, we had no outstanding jet fuel derivatives and we have not engaged in fuel derivative activity since 2015. There can be no assurance that we will be able to enter into fuel derivative contracts in the future if we are required or choose to do so. In the past, we have not had and in the future we may not have sufficient creditworthiness or liquidity to post the collateral necessary to hedge our fuel requirements. Even if we are able to hedge portions of our future fuel requirements, we cannot guarantee that our derivative contracts will provide any particular level of protection against increased fuel costs or that our counterparties will be able to perform under our derivative contracts, such as in the case of a counterparty’s insolvency. In a falling fuel price environment, we may be required to make cash payments to our counterparties which may impair our liquidity position and increase our costs.

We maintain a high daily aircraft utilization rate. Our average daily aircraft utilization was 12.3 hours for 2019, 12.1 hours for 2018 and 11.6 hours for 2017 and 12.4 hours for 2016.2017. Aircraft utilization is the average amount of time per day that our aircraft spend carrying passengers. Our revenue per aircraft can be increased by high daily aircraft utilization, which is achieved in part by reducing turnaround times at airports so we can fly more hours on average in a day. Aircraft utilization is reduced by delays and cancellations from various factors, many of which are beyond our control, including air traffic congestion at airports or other air traffic control problems, adverse weather conditions, increased security measures or breaches in security, international or domestic conflicts, terrorist activity, or other changes in business conditions. A significant portion of our operations are concentrated in markets such as South Florida, the Caribbean, Latin America and the Northeast and northern Midwest regions of the United States, which are particularly vulnerable to weather, airport traffic constraints and other delays. In addition, pulling aircraft out of service for unscheduled and scheduled maintenance, the occurrence of which will increase as our fleet ages, may materially reduce our average fleet utilization and require that we seek short-term substitute capacity at increased costs. Due to the relatively small size of our fleet and high daily aircraft utilization rate, the unavailability of aircraft and resulting reduced capacity could have a material adverse effect on our business, results of operations and financial condition.

As of December 31, 2018,2019, the average age of our aircraft was approximately 5.45.9 years. Our relatively new aircraft require less maintenance now than they will in the future. Our fleet will require more maintenance as it ages and our maintenance and repair expenses for each of our aircraft will be incurred at approximately the same intervals. For our leased aircraft, we expect that the final heavy maintenance events will be amortized over the remaining lease term rather than until the next estimated heavy maintenance event, because we account for heavy maintenance under the deferral method. This will result in significantly higher depreciation and amortization expense related to heavy maintenance in the last few years of the leases as compared to the costs in earlier periods. Moreover, because our current fleet was acquired over a relatively short period, significant maintenance that is scheduled on each of these planes is occurring at roughly the same time, meaning we will incur our most expensive scheduled maintenance obligations, known as heavy maintenance, across our present fleet around the same time. These more significant maintenance activities result in out-of-service periods during which our aircraft are dedicated to maintenance activities and unavailable to fly revenue service. In addition, the terms of some of our lease agreements require us to pay maintenance reserves to the lessor in advance of the performance of major maintenance, resulting in our recording significant prepaid deposits on our balance sheet. Depending on their recoverability, these maintenance reserves may be classified as supplemental rent. We expect scheduled and unscheduled aircraft maintenance expenses to increase over the next several years. Any significant increase in maintenance and repair expenses would have a material adverse effect on our business, results of operations and financial condition. Please see “Management’s Discussion and Analysis of Financial Condition and Results of Operations—Critical Accounting Policies and Estimates—Aircraft Maintenance, Materials and Repair Costs and Heavy Maintenance Amortization” and “—Maintenance Reserves.”

Many airlines, including the domestic traditional network airlines (American, Delta and United) have marketing alliances with other airlines, under which they market and advertise their status as marketing alliance partners. These alliances, such as

Airlines are subject to extensive and increasing regulatory and legal compliance requirements, both domestically and internationally, that involve significant costs. In the last several years, Congress has passed laws, and the DOT, FAA and TSA have issued regulations, relating to the operation of airlines that have required significant expenditures. We expect to continue to incur expenses in connection with complying with government regulations. Additional laws, regulations, taxes and increased airport rates and charges have been proposed from time to time that could significantly increase the cost of airline operations or reduce the demand for air travel. If adopted, these measures could have the effect of raising ticket prices, reducing revenue and increasing costs.

DOT has been aggressive in enforcing regulations for violations of the tarmac delay rules, passenger with disability rules, advertising rules and other consumer protection rules that could increase the cost of airline operations or reduce revenues. Additional rules on providing scheduling, fare and fee information to travel agents and metasearch sites may be issued in the future. Additional disability rules may be proposed, including with respectIn December 2019, the DOT issued a Notice of Proposed Rulemaking ("NPRM") to address access to lavatories on single-aisle aircraft. In addition, during 2014,We expect the FAA issued its final regulations governing pilot rest periodsDOT to issue an Advance Notice of Proposed Rulemaking ("ANPRM") soliciting comment and work hours for all airlines certificated under Part 121 of the Federal Aviation Regulations. The rule known as FAR 117, which became effective January 4, 2014, impacted the required amount and timing of rest periods for pilots between work assignments and modifies duty and rest requirements basedgathering updated information on the timecosts and benefits of day, numberrequiring airlines to increase the size of scheduled segments, flight types, time zones and other factors. Compliance with theselavatories on new single-aisle aircraft to be equivalent to that currently found on twin-aisle aircraft. Other additional disability rules may increase our costs, while failure to remainbe proposed in full compliance with these rules may subject us to fines or other enforcement action.the future.

Our growth strategy includes acquiring additional aircraft, increasing the frequency of flights and size of aircraft used in markets we currently serve, and expanding the number of markets we serve where our low cost structure would likely be successful. Effectively implementing our growth strategy is critical for our business to achieve economies of scale and to sustain or increase our profitability. We face numerous challenges in implementing our growth strategy, including our ability to:

Our growth is dependent upon our ability to maintain a safe and secure operation and requires additional personnel, equipment and facilities. An inability to hire and retain personnel, timely secure the required equipment and facilities in a cost-effective manner, efficiently operate our expanded facilities or obtain the necessary regulatory approvals may adversely affect our ability to achieve our growth strategy, which could harm our business. In addition, expansion to new markets may have other risks due to factors specific to those markets. We may be unable to foresee all of the existing risks upon entering certain new markets or respond adequately to these risks, and our growth strategy and our business may suffer as a result. In addition, our competitors may reduce their fares and/or offer special promotions to deter our entry into a new market or to stop our

Some of our target growth markets in the Caribbean and Latin America include countries with less developed economies that may be vulnerable to unstable economic and political conditions, such as significant fluctuations in gross domestic product, interest and currency exchange rates, high inflation, civil disturbances, government instability, nationalization and expropriation of private assets and the imposition of taxes or other charges by governments. The occurrence of any of these events in markets served by us and the resulting instability may adversely affect our ability to implement our growth strategy.

In 2008, in response to record high fuel prices and rapidly deteriorating economic conditions, we modified our growth plans by terminating our leases for seven aircraft. We incurred significant expenses relating to our lease terminations, and have incurred additional expenses to acquire new aircraft in place of those under the terminated leases as we expanded our network. We may in the future determine to reduce further our future growth plans from previously announced levels, which may impact our business strategy and future profitability.

We are highly dependent on technology and automated systems to operate our business and achieve low operating costs. These technologies and systems include our computerized airline reservation system, flight operations system, financial planning, management and accounting system, telecommunications systems, website, maintenance systems and check-in kiosks. The performance and reliability of our technology are critical to our ability to operate and compete effectively. In 2015, our Board of Directors approved a significant technology upgrade initiative meant to address our aging IT infrastructure. This initiative has and will continue to upgrade, replace, and enhance multiple older and outdated legacy systems and hardware. The execution of our strategic plans could be negatively affected by (i) our ability to timely and effectively implement, transition, and maintain related information technology systems and infrastructure; (ii) our ability to effectively balance our investment of incremental operating expenses and capital expenditures related to our strategies against the need to effectively control cost; and (iii) our dependence on third parties with respect to our ability to implement our strategic plans. We cannot assure you that our security measures, change control procedures, and disaster recovery plans will be adequate to prevent disruptions or delays. Disruption in or changes to these systems could result in an interruption to our operations or loss of important data. Any of the foregoing could result in a material adverse effect on our business, reputation, results of operations and financial condition.

In order for our operations to work efficiently, our website and reservation system must be able to accommodate a high volume of traffic, maintain secure information and deliver flight information with a high degree of reliability. Substantially all of our tickets are issued to passengers as electronic tickets. We depend on our reservation system, which is hosted and maintained under a long-term contract by a third-party service provider, to be able to issue, track and accept these electronic tickets. If our reservation system fails or experiences interruptions, and we are unable to book seats for any period of time, we could lose a significant amount of revenue as customers book seats on competing airlines. We have experienced short duration reservation system outages from time to time and may experience similar outages in the future. For example, in November 2010, we experienced a significant service outage with our third-party reservation service provider on the day before Thanksgiving, one of the industry’s busiest travel days and in August 2013, we experienced a 13-hour outage that affected our sales and customer service response times. We also rely on third-party service providers of our other automated systems for

In addition, our automated systems cannot be completely protected against events that are beyond our control, including natural disasters, cyber attacks, disruption of electrical grid or telecommunications failures. Substantial or sustained system failures could cause service delays or failures and result in our customers purchasing tickets from other airlines. We have implemented security measures and change control procedures and have disaster recovery plans; however, we cannot assure you that these measures are adequate to prevent disruptions. Disruption in, changes to or a breach of, these systems could result in a disruption to our business and the loss of important data. Moreover, in the event of system outages or interruptions, we may not be able to recover from our information technology and software providers all or any portion of the costs or business losses we may incur. Any of the foregoing could result in a material adverse effect on our business, results of operations and financial condition.

Actual or anticipated attacks may cause us to incur increasing costs, including costs to deploy additional personnel and protection technologies, train employees and engage third-party experts and consultants, or costs incurred in connection with the notifications to employees, suppliers or the general public as part of our notification obligations to the various governments that govern our business. Advances in computer capabilities, new technological discoveries, or other developments may result in the breach or compromise of technology used by us to protect transaction or other data. In addition, data and security breaches can also occur as a result of non-technical issues, including breaches by us or by persons with whom we have commercial relationships that result in the unauthorized release of personal or confidential information. Our reputation, brand and financial condition could be adversely affected if, as a result of a significant cyber event or other security issues: our operations are disrupted or shut down; our confidential, proprietary information is stolen or disclosed; we incur costs or are required to pay fines in connection with stolen customer, employee or other confidential information; we must dedicate significant resources to system repairs or increase cyber security protection; or we otherwise incur significant litigation or other costs.

In the processing of our customer transactions, we receive, process, transmit and store a large volume of identifiable personal data, including financial data such as credit card information. This data is increasingly subject to legislation and regulation, such as the California Consumer Privacy Act and the Fair Accurate Credit Transparency Act and Payment Card Industry legislation, typically intended to protect the privacy of personal data that is collected, processed and transmitted. More generally, we rely on consumer confidence in the security of our system, including our website on which we sell the majority of our tickets. Our business, results of operations and financial condition could be adversely affected if we are unable to comply with existing privacy obligations or legislation or regulations are expanded to require changes in our business practices.

Our business strategy includes expanding our portfolio of ancillary products and services. There can be no assurance that passengers will pay for additional ancillary products and services or that passengers will continue to choose to pay for the ancillary products and services we currently offer. Further, regulatory initiatives could adversely affect ancillary revenue opportunities. Failure to maintain our non-ticket revenues would have a material adverse effect on our results of operations and financial condition. Furthermore, if we are unable to maintain and grow our non-ticket revenues, we may not be able to execute our strategy to continue to lower base fares to address an underserved market. Please see “—Restrictions on or increased taxes applicable to charges for ancillary products and services paid by airline passengers and burdensome consumer protection regulations or laws could harm our business, results of operations and financial condition.”

We are highly dependent on markets served from airports where we maintain a large presence. Our results of operations may be affected by actions taken by governmental or other agencies or authorities having jurisdiction over our operations at airports, including, but not limited to:

In general, any changes in airport operations could have a material adverse effect on our business, results of operations and financial condition.

We have entered into agreements with third-party service providers to furnish certain facilities and services required for our operations, including ground handling, catering, passenger handling, engineering, maintenance, refueling, reservations and airport facilities as well as administrative and support services. We are likely to enter into similar service agreements in new markets we decide to enter, and there can be no assurance that we will be able to obtain the necessary services at acceptable rates.

Although we seek to monitor the performance of third parties that provide us with our reservation system, ground handling, catering, passenger handling, engineering, maintenance services, refueling and airport facilities, the efficiency, timeliness and quality of contract performance by third-party service providers are often beyond our control, and any failure by our service providers to perform their contracts may have an adverse impact on our business and operations. For example, in 2008, our call center provider went bankrupt. Though we were able to quickly switch to an alternative vendor, we experienced a significant business disruption during the transition period and a similar disruption could occur in the future if we changed call center providers or if an existing provider ceased to be able to serve us. We expect to be dependent on such third-party arrangements for the foreseeable future.

We are exposed to potential significant losses in the event that any of our aircraft is subject to an emergency, accident, terrorist incident or other similar incident, and significant costs related to passenger claims, repairs or replacement of a damaged aircraft and its temporary or permanent loss from service. There can be no assurance that we will not be affected by such events or that the amount of our insurance coverage will be adequate in the event such circumstances arise and any such event could cause a substantial increase in our insurance premiums. Please see “—Increases in insurance costs or significant reductions in coverage could have a material adverse effect on our business, financial condition and results of operations.” In addition, any future aircraft emergency, accident or similar incident, even if fully covered by insurance or even if it does not involve our airline, may create a public perception that our airline or the equipment we fly is less safe or reliable than other transportation alternatives, or could cause us to perform time consuming and costly inspections on our aircraft or engines which could have a material adverse effect on our business, results of operations and financial condition.

In the past, we have experienced a relatively high number of customer complaints related to, among other things, our customer service and reservations and ticketing systems. In particular, we generally experience a higher volume of complaints when we make changes to our unbundling policies, such as charging for baggage. In addition, in 2009, we entered into a consent order with the DOT for our procedures for bumping passengers from oversold flights and our handling of lost or damaged baggage. Under the consent order, we were assessed a civil penalty of $375,000, of which we were required to pay $215,000 based on an agreement with the DOT and not having similar violations in the year after the date of the consent order. Further, media reports about incidents on our aircraft unrelated to customer complaints could negatively impact our reputation and our operations. If we do not meet our customers' expectations with respect to reliability and service, customers could decide not to fly with us, which would materially adversely affect our business and reputation.

One of the elements of our business strategy is to save costs by operating a single-family aircraft fleet - currently Airbus A320-family, single-aisle aircraft, powered by engines manufactured by IAE and Pratt & Whitney. If any of Airbus, IAE, or Pratt & Whitney become unable to perform its contractual obligations, or if we are unable to acquire or lease aircraft or engines from these or other owners, operators or lessors on acceptable terms, we would have to find other suppliers for a similar type of aircraft or engine. If we have to lease or purchase aircraft from another supplier, we would lose the significant benefits we derive from our current single fleet composition. We may also incur substantial transition costs, including costs associated with retraining our employees, replacing our manuals and adapting our facilities and maintenance programs. Our operations could also be harmed by the failure or inability of aircraft, engine and parts suppliers to provide sufficient spare parts or related support services on a timely basis, particularly in connection with new-generation introductory technology. Our business would be significantly harmed if a design defect or mechanical problem with any of the types of aircraft, engines or components currently on order or that we operate were discovered that would halt or delay our aircraft delivery stream or that would ground any of our aircraft while the defect or problem was corrected, assuming it could be corrected at all. For example, duringSince the fourth quarteraddition of A320neo aircraft in 2016, and continuing through early 2018,we have experienced introductory issues with the new-generation PW1100G-JM engines, designed and manufactured by Pratt & Whitney, which has resulted in the intermittent groundingdiminished service availability of certain of our A320neosuch aircraft. In February 2018, all five of our A320neo aircraft became fully operational and the aircraft continue to be in service. We continuously work with Pratt & Whitney to secure support and relief in connection with possible engine related operation disruptions. Due in

A significant portion of our operations are conducted to and from the domestic U.S., Caribbean or Latin American markets. Our business, results of operations and financial condition could be harmed if we lost our authority to fly to these

We carry insurance for third-party liability, passenger liability, property damage and all-risk coverage for damage to our aircraft. As a result of the September 11, 2001 terrorist attacks, aviation insurers significantly reduced the amount of insurance coverage available to commercial air carriers for liability to persons other than employees or passengers for claims resulting from acts of terrorism, war or similar events (war risk insurance). Accordingly, our insurance costs increased significantly and our ability to continue to obtain certain types of insurance remains uncertain. While the price of commercial insurance has declined since the period immediately after the terrorist attacks, in the event commercial insurance carriers further reduce the amount of insurance coverage available to us, or significantly increase its cost, we would be adversely affected. We currently maintain commercial airline insurance with several underwriters. However, there can be no assurance that the amount of such coverage will not be changed, or that we will not bear substantial losses from accidents. We could incur substantial claims resulting from an accident in excess of related insurance coverage that could have a material adverse effect on our results of operations and financial condition. Renewing coverage may result in higher premiums and more restrictive terms. Our business, results of operations and financial condition could be materially adversely affected if we are unable to obtain adequate insurance.

We are subject to increasingly stringent federal, state, local and foreign laws, regulations and ordinances relating to the protection of the environment, including those relating to emissions to the air, discharges to surface and subsurface waters, safe drinking water and the management of hazardous substances, oils and waste materials. Compliance with all environmental laws and regulations can require significant expenditures and any future regulatory developments in the United States and abroad could adversely affect operations and increase operating costs in the airline industry. For example, climate change legislation was previously introduced in Congress and such legislation could be re-introduced in the future by Congress and state legislatures, and could contain provisions affecting the aviation industry, compliance with which could result in the creation of substantial additional costs to us. Similarly, the Environmental Protection Agency issued a rule that regulates larger emitters of greenhouse gases. Future operations and financial results may vary as a result of such regulations. Compliance with these regulations and new or existing regulations that may be applicable to us in the future could increase our cost base and could have a material adverse effect on our business, results of operations and financial condition.

Governmental authorities in several U.S. and foreign cities are also considering or have already implemented aircraft noise reduction programs, including the imposition of nighttime curfews and limitations on daytime take-offs and landings. We have been able to accommodate local noise restrictions imposed to date, but our operations could be adversely affected if locally-imposed regulations become more restrictive or widespread.

Our business is labor intensive. We require large numbers of pilots, flight attendants, maintenance technicians and other personnel. The airline industry has from time to time experienced a shortage of qualified personnel, particularly with respect to pilots and maintenance technicians. In addition, we may face high employee turnover. We may be required to increase wages and/or benefits in order to attract and retain qualified personnel. If we are unable to hire, train and retain qualified employees, our business could be harmed and we may be unable to implement our growth plans.

In addition, as we hire more people and grow, we believe it may be increasingly challenging to continue to hire people who will maintain our company culture. Our company culture, which we believe is one of our competitive strengths, is important to providing high-quality customer service and having a productive, accountable workforce that helps keep our costs low. As we continue to grow, we may be unable to identify, hire or retain enough people who meet the above criteria, including those in management or other key positions. Our company culture could otherwise be adversely affected by our growing operations and geographic diversity. If we fail to maintain the strength of our company culture, our competitive ability and our business, results of operations and financial condition could be harmed.

Our success depends to a significant extent upon the efforts and abilities of our senior management team and key financial and operating personnel. In particular, we depend on the services of our senior management team. Competition for highly qualified personnel is intense, and the loss of any executive officer, senior manager, or other key employee without adequate replacement or the inability to attract new qualified personnel could have a material adverse effect on our business, results of operations and financial condition. We do not maintain key-person life insurance on our management team.

As a public company, we incur significant legal, accounting and other expenses, including costs associated with public company reporting requirements. We also have incurred and will continue to incur costs associated with the Sarbanes-Oxley Act of 2002, as amended, the Dodd-Frank Wall Street Reform and Consumer Protection Act and related rules implemented or to be implemented by the SEC and the New York Stock Exchange. The expenses incurred by public companies generally for reporting and corporate governance purposes have been increasing. We expect these rules and regulations to increase our legal and financial compliance costs and to make some activities more time-consuming and costly. These laws and regulations could also make it more difficult or costly for us to obtain certain types of insurance, including director and officer liability insurance, and we may be forced to accept reduced policy limits and coverage or incur substantially higher costs to obtain the same or similar coverage. These laws and regulations could also make it more difficult for us to attract and retain qualified persons to serve on our board of directors, our board committees, or as our executive officers and may divert management’s attention. Furthermore, if we are unable to satisfy our obligations as a public company, we could be subject to delisting of our common stock, fines, sanctions and other regulatory action and potentially civil litigation.

The market price of our common stock may fluctuate substantially due to a variety of factors, many of which are beyond our control, including:

The stock markets in general have experienced substantial volatility that has often been unrelated to the operating performance of particular companies. These types of broad market fluctuations may adversely affect the trading price of our common stock.

In the past, stockholders have sometimes instituted securities class action litigation against companies following periods of volatility in the market price of their securities. Any similar litigation against us could result in substantial costs, divert management’s attention and resources and harm our business or results of operations.

The trading market for our common stock depends in part on the research and reports that securities or industry analysts publish about us or our business. If one or more of the analysts who cover us downgrade our stock or publish inaccurate or unfavorable research about our business, our stock price would likely decline. If one or more of these analysts cease coverage of our company or fail to publish reports on us regularly, demand for our stock could decrease, which might cause our stock price and trading volume to decline.

Our amended and restated certificate of incorporation and amended and restated bylaws contain provisions that may make it difficult to remove our board of directors and management and may discourage or delay “change of control” transactions, which could adversely affect the price of our common stock. These provisions include, among others:

To comply with restrictions imposed by federal law on foreign ownership of U.S. airlines, our amended and restated certificate of incorporation and amended and restated bylaws restrict voting of shares of our common stock by non-U.S. citizens. The restrictions imposed by federal law currently require that no more than 25% of our stock be voted, directly or indirectly, by persons who are not U.S. citizens, and that our president and at least two-thirds of the members of our board of directors and senior management be U.S. citizens. Our amended and restated bylaws provide that the failure of non-U.S. citizens to register their shares on a separate stock record, which we refer to as the “foreign stock record,” would result in a suspension of their voting rights in the event that the aggregate foreign ownership of the outstanding common stock exceeds the foreign ownership restrictions imposed by federal law.

Our amended and restated bylaws further provide that no shares of our common stock will be registered on the foreign stock record if the amount so registered would exceed the foreign ownership restrictions imposed by federal law. If it is determined that the amount registered in the foreign stock record exceeds the foreign ownership restrictions imposed by federal law, shares will be removed from the foreign stock record in reverse chronological order based on the date of registration therein, until the number of shares registered therein does not exceed the foreign ownership restrictions imposed by federal law. As of December 31, 2018,2019, we believe we were in compliance with the foreign ownership rules.

As of December 31, 2018,2019, there are no shares of non-voting common stock outstanding. When shares of non-voting common stock are outstanding, the holders of such stock may convert such shares, on a share-for-share basis, in the order reflected on our foreign stock record as shares of common stock are sold or otherwise transferred by non-U.S. citizens to U.S. citizens.

Our amended and restated certificate of incorporation also specifies that the Court of Chancery of the State of Delaware shall be the exclusive forum for substantially all disputes between us and our stockholders.

We have never declared or paid cash dividends on our common stock. We currently intend to retain our future earnings, if any, to finance the further development and expansion of our business and fund share repurchases under programs approved by our Board of Directors. We do not intend to pay cash dividends in the foreseeable future. Any future determination to pay dividends will be at the discretion of our board of directors and will depend on our financial condition, results of operations, capital requirements, restrictions contained in current or future financing instruments, business prospects and such other factors as our Board of Directors deems relevant. The timing of any share repurchases under share repurchase programs will depend upon market conditions, our capital allocation strategy and other factors.