We have elected to provide access to our proxy materials over the Internet. Accordingly, on or about April 27, 2022,28, 2023, we are mailingcommencing delivery of a Notice of Internet Availability of Proxy Materials to most of our stockholders of record, and paper copies of the proxy materials to certain other stockholders of record. All stockholders will have the ability to access the proxy materials on the website referred to in the notice or request to receive a printed set of the proxy materials. You can find instructions on how to request a printed copy by mail or electronically on the notice and on the website referred to in the notice, including an option to request paper copies on an ongoing basis. On April 27, 2022,28, 2023, we intend to make this proxy statement available on the Internet and to commence mailingdelivery of the Notice of Internet Availability of Proxy Materials to all stockholders entitled to vote at the Annual Meeting. We intend to maildeliver this proxy statement, together with a proxy card, to those stockholders entitled to vote at the Annual Meeting who have properly requested paper copies of such materials, within three business days of such request.

YOUR VOTE IS VERY IMPORTANT. You should submit your proxy even if you plan to attend the Annual Meeting in person. If you are a stockholder of record on the Record Date, you are invited to attend the Annual Meeting in person and vote your shares during the Annual Meeting. If you properly give your proxy and submit it to us in time to vote, one of the individuals named as your proxy will vote your shares as you have directed.

All shares entitled to vote and represented by properly submitted proxies (including those submitted electronically, telephonically and in writing), and not revoked or superseded, will be voted at the Annual Meeting in accordance with the instructions indicated on those proxies. If no direction is indicated on a proxy, your shares will be voted as follows:

The proxy gives each of Sharat Sharan, Steven Vattuone and William Weesner discretionary authority to vote your shares in accordance with their best judgment with respect to all additional matters that might come before the Annual Meeting. If you receive more than one proxy card or Notice of Internet Availability of Proxy Materials, it means you hold shares that are registered in more than one account. To ensure that all of your shares are voted, sign and return each proxy card or, if you submit a proxy by telephone or the Internet, submit one proxy for each proxy card or Notice of Internet Availability of Proxy Materials you receive.

If you are a stockholder of record, you may revoke your proxy at any time before your proxy is voted at the Annual Meeting by taking any of the following actions:

Written notices of revocation and other communications with respect to the revocation of Company proxies should be addressed to:

If your shares are held in “street name,” you may change your vote by submitting new voting instructions to your broker. You must contact your broker to find out how to do so. See below regarding how to vote live if your shares are held in street name.

If you are a stockholder of record (or a registered stockholder), we will verify your ownership at the meeting in our list of stockholders as of the Record Date (April 13, 2022)25, 2023). If your shares are held through a broker, you must bring proof of your ownership of the shares as of the Record Date (April 13, 2022)25, 2023). This proof could consist of, for example, brokerage firm account statement or a letter from your broker confirming your ownership as of the Record Date.

In order to allow ample time for check-in, you will need to plan to arrive at 50 Beale Street, 8th Floor, San Francisco, California 94105 on June 10, 2022,23, 2023, no later than 8:00 a.m. Pacific Time. At the pre-registration table, you will be asked to complete a pandemic screening form. Next, at the registration table, you will need to present a government-issued photo identification, along with proof of your stock ownership.

Upon completion of these steps, you will be issued a visitor badge, which you must wear at all times. Prohibited items include backpacks, purses or bags larger than 12”x 6”x 12,” coolers and camera cases. Visitors must adhere to all ON24, Inc. COVID-19 Safety Requirements in effect at the time of their visit, which may include social distancing and/or face covering requirements.

Visitors must always be escorted by ON24, Inc. security or personnel, and should return the visitor badge when leaving the building after the Annual Meeting is adjourned.

Our board of directors is soliciting proxies for the Annual Meeting from our stockholders. We will bear the entire cost of soliciting proxies from our stockholders. In addition to the solicitation of proxies by delivery of the Notice of Internet Availability of Proxy Materials or proxy statement, by mail, we will request that brokers that hold shares of our common stock, which are beneficially owned by our stockholders, send Notices of Internet Availability of Proxy Materials, proxies and proxy materials to those beneficial owners and secure those beneficial owners’ voting instructions. We will reimburse those record holders for their reasonable expenses. We may use several of our regular employees, who will not be specially compensated, to solicit proxies from our stockholders, either personally or by telephone, Internet, facsimile or special delivery letter. It is contemplated that additional solicitation of proxies will be made in the same manner under the engagement and direction of Okapi Partners, 1212 Avenue of the Americas, Floor 24, New York, NY 10036, at an anticipated cost of $12,500,$13,500, plus reimbursement of out-of-pocket expenses.

StockholdersThose who wish to communicate with our board of directors or specific individual directors may do so by letter sent to our principal executive offices, addressed to the attention of our Corporate Secretary. Our Corporate Secretary reviews all communications and forwards them to the intended recipient(s) consistent with a screening policy, which provides that sales materials, routine items, and items unrelated to the duties and responsibilities of the board of directors are not relayed to directors.

This proxy statement contains “forward-looking statements” (as defined in the Private Securities Litigation Reform Act of 1995). These statements are based on our current expectations and involve risks and uncertainties, which may cause results to differ materially from those set forth in the statements. The forward-looking statements may include statements regarding actions to be taken by us. We undertake no obligation to publicly update any forward-looking statement, whether as a result of new information, future events or otherwise, except as required by law. Forward-looking statements should be evaluated together with the many uncertainties that affect our business, particularly those mentioned in the risk factors in Item 1A of our Annual Report on Form 10-K for the year ended December 31, 2021,2022, and in our periodic reports on Form 10-Q and our current reports on Form 8-K.

Cynthia Paul and Ronald Mitchell were also appointed to our board of directors in April 2022 to fillMarch 2023 in connection with the Cooperation Agreement (the “Cooperation Agreement”) with Indaba Capital Management, L.P. (“Indaba”), dated March 11, 2023. Ms. Paul filled a newly-created Class IIIII vacancy and she stands for election this year. Mr. Mitchell filled a newly-created Class I vacancy for a term expiring at our 2025 annual meeting of stockholders. Also in connection with the Cooperation Agreement, Mr. Mitchell submitted an irrevocable letter of resignation, effective at the 2024 annual meeting of stockholders, if the Company delivers notice to Indaba and Mr. Mitchell that the board of directors does not wish for Mr. Mitchell to continue as a director after the 2024 annual meeting of stockholders. As part of the Cooperation Agreement, Indaba agreed, among other things, (i) to customary standstill provisions until the date pursuant to which stockholder nominations for director elections are permitted pursuant to the Company’s Bylaws with respect the Company’s 2024 annual meeting of stockholders and (ii) to vote its shares in favor of the board of directors’ slate of directors at the Annual Meeting.

Our Certificate of Incorporation and Bylaws provide that our directors may only be removed from our board of directors for cause by the affirmative vote of at least 66.7%66 2/3% of the voting power of all of our then-outstanding shares of capital stock entitled to vote generally in the election of directors, voting together as a single class. In addition, our Certificate of Incorporation will provideprovides that, subject to the rights granted to one or more series of preferred stock then outstanding, any newly created directorship on the board of directors that results from an increase in the number of directors and any vacancies on our board of directors will be filled only by the affirmative vote of a majority of the remaining directors, even if less than a quorum, or by a sole remaining director.

Our board of directors has determined that each member of our board of directors, except Sharat Sharan, is an “independent director,” as defined under the rules of the New York Stock Exchange (“NYSE”) and the Securities and Exchange Commission (“SEC”). In making this determination, our board of directors applied the standards set forth under Rule 10A-3 of the Securities Exchange Act of 1934, as amended (“Exchange Act”) and related SEC and NYSE rules. Our board of directors considered all relevant facts and circumstances known to it in evaluating the independence of these directors, including their current and historical employment, any compensation we have paid to them, any transactions we have had with them, their beneficial ownership of our capital stock, their ability to exert control over us, all other material relationships they have had with us and the same facts with respect to their immediate families.

The composition and functioning of our board of directors and each of our committees complies with all applicable requirements of the NYSE and the rules and regulations of the SEC.

In accordance with our Certificate of Incorporation, our board of directors is divided into three classes with staggered three-year terms. At each annual meeting of the stockholders, the successors to the directors whose terms will then expire will be elected to serve from the time of election and qualification until the third annual meeting following their election. Our directors are divided among the three classes as follows:

Any increase or decrease in the number of directors will be distributed among the three classes so that, as nearly as possible, each class will consist of one-third of the directors. This classification of our board of directors may have the effect of delaying or preventing changes in control of our company. As set forth in Proposal No. 2, we are proposing that our stockholders approve and adopt an amendment and restatement of our Certificate of Incorporation to declassify our board of directors.

Our non-management directors meet regularly in executive sessions without management, to consider such matters as they deem appropriate. Our Lead Independent Director, Mr. Trempont,Arora, presides over all executive sessions.

Our board of directors has established an audit committee, a compensation committee and a nominating and corporate governance committee, each of which operates pursuant to a written charter adopted by our board of directors. Our board of directors may also establish other committees from time to time to assist the board of directors. The composition and functioning of all of our committees comply with all applicable requirements of the Sarbanes-Oxley Act, NYSE and SEC rules and regulations. Each committee has a charter, which is available on the “Governance” section of our website at https://investors.www.on24.com/governance/governance-documents. Information contained on, or that can be accessed through, our website is not part of and is not incorporated by reference into this proxy statement, and you should not consider information on our website to be part of this proxy statement.

Messrs. Zwarenstein, Federman and Trempont serve on the audit committee, which is chaired by Mr. Zwarenstein. The audit committee met fivefour times during fiscal year 2021,2022, and each member attended all meetings. Our board of directors has determined that each member of the audit committee is “independent” as that term is defined in the SEC and the NYSE rules, meets the heightened independence requirements for audit committees required under Section 10A of the Exchange Act and related SEC and the NYSE rules, and has sufficient knowledge in financial and auditing matters to serve on the audit committee. Our board of directors has designated Mr. Zwarenstein as an “audit committee financial expert,” as defined under the applicable rules of the SEC. The audit committee’s responsibilities include:

Messrs. Trempont, Arora, Zingale and Zwarenstein serve on the compensation committee, which is chaired by Mr. Trempont. The compensation committee met five times during fiscal year 2021,2022, and each member attended all meetings.meetings held in 2022 during the period that they served. Our board of directors has determined that each member of the compensation committee is “independent” as that term is defined in SEC and the NYSE rules, meets the heightened independence requirements for compensation committee purposes under Section 10C of the Exchange Act and related SEC and the NYSE rules, and is a “non-employee director” under Rule 16b-3 under the Exchange Act. The compensation committee’s responsibilities include:

Ms. Persson and Messrs. Trempont, Arora, Federman and FedermanMitchell serve on the nominating and corporate governance committee, which is chaired by Mr. Trempont. The nominating and corporate governance committee met four times during fiscal year 2021,2022, and each member attended all meetings.at least 75% of the meetings held in 2022 during the period that they served. Our board of directors has determined that each member of the nominating and corporate governance committee is “independent” as defined in the NYSE rules. The nominating and corporate governance committee’s responsibilities include:

The nominating and corporate governance committee will consider director candidates recommended by stockholders on the same basis that it evaluates other nominees for director. Stockholders who wish to recommend a candidate to our nominating and corporate governance committee for consideration for nomination should send to us, at our principal executive offices, information regarding the candidate. In order to identify potential director candidates, the committee may utilize its or our existing networks or retain a third-party recruiting firm.

Pursuant to our Corporate Governance Guidelines, when considering the nominees for election as directors at an annual meeting or to fill an existing vacancy, the nominating and corporate governance committee reviews the needs of our board of directors for various skills, background, experience and expected contributions and the qualification standards established from time to time by the nominating and corporate governance committee. When reviewing potential nominees, including incumbents, the nominating and corporate governance committee considers the perceived needs of our board of directors as a whole and the candidate’s relevant background, experience, skills and expected contributions

to our board of directors. The nominating and corporate governance committee’s goal is to assemble a board of directors that brings to our company a diversity of experience in areas that are relevant to our activities. Directors should possess the highest personal and professional ethics, integrity and values and be committed to representing the long-term interests of our stockholders. They must have an

We are dedicated to making sustainable and equitable choices that leave an impact that we can be proud of. Our technologies help reduce the need for people to travel to in-person conferences and physical customer locations to conduct their business. For more information regarding our sustainability initiatives, commitment to social impact and responsible corporate governance, please see our website at www.on24.com/corporate-responsibility.

In addition, each new non-employee director who joins our board of directors automatically receives an RSU for common stock having a value of $450,000 based on the average fair market value of our common stock for the 20 trading days prior to and ending on the date of grant (the “Initial RSU”). Each Initial RSU will vest over three years, with one-third of the Initial RSU vesting on the first, second, and third anniversary of the date of grant. Moreover, on the date of each annual meeting of our stockholders, each person who is then a non-employee director will automatically receive an RSU for common stock having a value of $175,000 based on the average fair market value of the underlying common stock for the 20 trading days prior to and ending on the date of grant (the “Annual RSU”). Each Annual RSU will vest on the earlier of (i) the date of the following year’s annual meeting of our stockholders (or the date immediately prior to the next annual meeting of our stockholders if the non-employee director’s service as a director ends at such meeting due to the director’s failure to be re-elected or the director not standing for re-election); or (ii) the first anniversary of the date of grant. Vesting of Initial RSUs and Annual RSUs is subject to the non-employee director’s continuous service on each applicable vesting date. For each non-employee director who remains in continuous service with us until immediately prior to a “change of control” (as defined in our 2021 Equity Incentive Plan (the “2021 Plan”)), the shares subject to his or her then outstanding equity awards will become fully vested as of immediately prior to the change of control.

We will reimburse each non-employee director for ordinary, necessary, and reasonable out-of-pocket travel expenses to cover in-person attendance at, and participation in, meetings of our board of directors and any of its committees.

The board of directors and the nominating and corporate governance committee believe the skills, qualities, attributes and experience of our directors provide us with business acumen and a diverse range of perspectives to engage each other and management to effectively address our evolving needs and represent the best interests of our stockholders.

Vacancies on the board, including any vacancy created by an increase in the size of the board, may be filled only by a majority of the directors remaining in office, even though less than a quorum of the board, or a sole remaining director. A director elected by the board to fill a vacancy will serve until the next election of the class of directors for which such director was chosen and until such director’s successor is elected and qualified, or until such director’s earlier retirement, resignation, disqualification, removal or death.

If any nominee should become unavailable for election prior to the Annual Meeting, an event that currently is not anticipated by the board of directors, the proxies will be voted in favor of the election of a substitute nominee or nominees proposed by the board of directors or the number of directors may be reduced accordingly. Each nominee has agreed to serve if elected and the board of directors has no reason to believe that any nominee will be unable to serve.

Our continuing directors and their respective ages (as of April 27, 2022)March 31, 2023) and designation are as follows:

Set forth below is biographical information for each nominee and a summary of the specific qualifications, attributes, skills and experiences which led our board of directors to conclude that each nominee should serve on the board at this time. In order to better understand the biographical information set forth below, please note that ON24, Inc. was formed in January 1998 and our IPO closed in February 2021.

The compensation committee conducted its annual review of the base salaries of the Company’s named executive officers in the first quarter of 2022. The following table sets forth the 2020, 2021, 2022 and 20222023 base salaries for each of Mr. Sharan, Mr. Sahasi and Mr. Blackie.

We grant annual incentives intended to create a direct correlation between the executive’s role and responsibilities and the ability to earn variable pay. During the fiscal year ended December 31, 2021,2022, our named executive officers were eligible to earn annual incentives based on the achievement of a weighted mix of corporate performance objectives relating to net ARR growth and non-GAAP EBIT. For the fiscal year ended December 31, 2021,2022, Sharat Sharan, James Blackie and Jayesh Sahasi had an annual bonus opportunity targeted at 100%95%, 77.8%90% and 59.8%70%, respectively, of each’s base salary. We have based the annual bonus opportunity for each of our named executive officers 100%entirely on the achievement of these corporate performance objectives.

We grant equity incentive awards when we determine it is appropriate to do so in order to align the interests of our named executive officers with those of our stockholders and to motivate them to make impactful contributions to our performance. These awards are all subject to time-based vesting conditions and in the case of performance awards (PSUs), they are also subject to certain performance conditions.

We are party to a continuing employment letter with Mr. Sharan, our Chief Executive Officer and a member of our board of directors. The employment letter does not have a specific term. Under the employment letter, Mr. Sharan’s base salary is $495,000$520,000 subject to annual review and his annual target bonus is $495,000. Mr. Sharan is eligible to participate in our standard health and welfare benefits programs.

In the event of an “involuntary termination” or if we terminate his employment without “cause,” Mr. Sharan is entitled to receive, subject to his execution of a general release of claims, a severance payment equivalent to 12 months of his base salary (or 18 months for a “change of control termination”), 100% of his target bonus (or 150% for a “change of control termination”), a pro rata portion of his target bonus for the year, and 12 months of COBRA premiums (18 months in the event of a change of control termination), and 75% of his then unvested equity awards shall immediately vest and become exercisable. In these circumstances, Mr. Sharan will be permitted to purchase any vested portion of those awards through the date those awards are scheduled to expire.

If we consummate a “change of control” while Mr. Sharan is employed or we enter into an agreement to effect a change of control within 90 days following termination of his employment that we ultimately consummate, then immediately prior to the consummation of such change of control, 75% of his then unvested equity awards shall immediately vest and become exercisable. In the event of a change of control termination, all of Mr. Sharan’s unvested equity awards shall immediately vest and become exercisable.

Under Mr. Sharan’s employment letter:

We are party to a continuing employment letter with Mr. Blackie, our Chief Revenue Officer. The employment letter does not have a specific term and provides that Mr. Blackie’s employment is at-will. Mr. Blackie’s current annual base salary is $475,000 and his target bonus is equal to a percentage of his base salary, as determined by our compensation committee. Mr. Blackie is eligible to participate in our standard health and welfare benefits programs.

We are party to a continuing employment letter with Mr. Sahasi, our Chief Technology Officer. The employment letter does not have a specific term and provides that Mr. Sahasi’s employment is at-will. Mr. Sahasi’s current annual base salary is $475,000 and his target bonus is equal to a percentage of his base salary, as determined by our compensation committee. Mr. Sahasi is eligible to participate in our standard health and welfare benefits programs.

We have entered into severance program agreements with our executive officers, excluding Mr. Sharan. Under the severance program agreements, if we terminate the employment of our executive officers without “cause,” he or she is entitled to receive a severance payment equivalent to six months of his or her base salary and reimbursement of up to six months of COBRA premiums, in addition to standard entitlements such as earned but unpaid wages, including any bonus he or she is otherwise entitled to, reimbursement for unpaid expenses incurred and payment of other vested benefits.

If, on or within twelve months of a “change in control,” an executive officer’s employment is terminated without “cause,” or if he or she resigns for “good reason,” he or she is entitled to receive a severance payment equivalent to one year of his or her then-current base salary, accelerated vesting of 100% of the shares underlying his or her then-unvested equity awards and reimbursement of up to twelve months of COBRA premiums, in addition to standard entitlements such as earned but unpaid wages, including any bonus he or she is otherwise entitled to, reimbursement for unpaid expenses incurred and payment of other vested benefits.

Under the severance program, “cause” means (i) theft, dishonesty, willful misconduct, breach of fiduciary duty for personal profit, or falsification of any Participating Company documents or records; (ii) the executive’s material failure to abide by our code of conduct or other policies (including, without limitation, policies relating to confidentiality and reasonable workplace conduct); (iii) the executive’s unauthorized use, misappropriation, destruction or diversion of any tangible or intangible asset or corporate opportunity of a ours (including, without limitation, the executive’s improper use or disclosure of our or proprietary information); (iv) any intentional act by the executive which has a material detrimental effect on our reputation or business; (v) the executive’s repeated failure or inability to perform any reasonable assigned duties after written notice from us of, and a reasonable opportunity to cure, such failure or inability; (vi) any material breach by the executive of any employment or service agreement between the executive and us, which breach is not cured pursuant to the terms of such agreement; or (vii) the executive’s conviction (including any plea of guilty or nolo contendere) of any criminal act involving fraud, dishonesty, misappropriation or moral turpitude, or which impairs the executive’s ability to perform his or her duties with us.

Under the severance program, “change in control” means (i) a transaction in which the stockholders of ON24 immediately before the transaction do not retain immediately after the transaction direct or indirect beneficial ownership of more than 50% of the total combined voting power of the outstanding securities entitled to vote generally in the election of Directors or the entity to which all or substantially all of our assets were transferred or (ii) a date specified by the board of directors following approval by the stockholders of a plan of complete liquidation or dissolution of ON24, unless a majority of the members of the board of directors of the continuing, surviving or successor entity or parent thereof, immediately after such transaction is comprised of incumbent directors. This offering will not constitute a change in control under the severance program.

Under the severance program agreement, “good reason” means resignation from employment with us following the occurrence of any of the following events without the executive’s prior written consent: (i) a significant reduction in the executive’s duties, position or responsibilities in effect immediately prior to such reduction, other than where the executive is asked to assume substantially similar duties and responsibilities in a larger entity after such change in control (which may involve a different title); (ii) a material reduction in current base salary; or (iii) a relocation to a worksite that is more than 50 miles from the then-existing worksite.

The following table sets forth information regarding outstanding option awards held by our named executive officers as of December 31, 2021.2022.

In connection with our IPO, we adopted our 2021 Plan, effective in February 2021. We intend to use the 2021 Plan to provide incentives that will assist us to attract, retain, and motivate employees, including officers, consultants, and directors. We may provide these incentives through the grant of stock options, stock appreciation rights, restricted stock, RSUs, performance shares, and units and other cash-based or share-based awards. In addition, the 2021 Plan contains a mechanism through which we may adopt a deferred compensation arrangement in the future.

A total of 6,400,000 shares of our common stock were initially authorized and reserved for future issuance under the 2021 Plan. This reserve will automatically increaseincreases on January 1, 2022 and each subsequent anniversary through 2031, by an amount equal to the smaller of:

Appropriate adjustments will be made in the number of authorized shares and other numerical limits in the 2021 Plan and in outstanding awards to prevent dilution or enlargement of participants’ rights in the event of a stock split or other change in our capital structure. Shares subject to awards which expire or are cancelled or forfeited will again become available for issuance under the 2021 Plan.

The shares available under the 2021 Plan will not be reduced by awards settled in cash, but will be reduced by shares withheld to satisfy tax withholding obligations with respect to stock options and stock appreciation rights (but not other types of awards). The gross number of shares issued upon the exercise of stock appreciation rights or options exercised by means of a net exercise or by tender of previously owned shares will be deducted from the shares available under the 2021 Plan.

The 2021 Plan generally will be administered by the compensation committee of our board of directors. Subject to the provisions of the 2021 Plan, the compensation committee will determine in its discretion the persons (other than the CEO and members of our board of directors) to whom and the times at which awards are granted, the sizes of such awards and all of their terms and conditions. The compensation committee will have the authority to construe and interpret the terms of the 2021 Plan and awards granted under it. The 2021 Plan provides, subject to certain limitations, for indemnification by us of any director, officer, or employee against all reasonable expenses, including attorneys’ fees, incurred in connection with any legal action arising from such person’s action or failure to act in administering the 2021 Plan.

During any year, no non-employee director may be granted one or more awards pursuant to the 2021 Plan which, taken together with any cash compensation paid to such non-employee director during such year, exceeds $1,000,000.

The 2021 Plan authorizes the compensation committee, without further stockholder approval, to provide for the cancellation of stock options or stock appreciation rights with exercise prices in excess of the fair market value of the underlying shares of common stock on the date of grant in exchange for new options or other equity awards with exercise prices equal to the fair market value of the underlying common stock on the date of grant or a cash payment.

Awards may be granted under the 2021 Plan to our employees, including officers, directors, or consultants or those of any present or future parent or subsidiary corporation or other affiliated entity. All awards will be evidenced by a written agreement between us and the holder of the award and may include any of the following:

In the event of a change in control as described in the 2021 Plan, the acquiring or successor entity may assume or continue all or any awards outstanding under the 2021 Plan or substitute substantially equivalent awards. The compensation committee may provide for the acceleration of vesting of any or all outstanding awards upon such terms and to such extent as it determines, except that the vesting of all awards held by members of the board of directors who

are not employees will automatically be accelerated in full. Any awards that are not assumed, continued, or substituted for in connection with a change in control or are not exercised or settled prior to the change in control will terminate effective as of the time of the change in control. The 2021 Plan also authorizes the compensation committee, in its discretion and without the consent of any participant, to cancel each or any outstanding award denominated in shares upon a change in control in exchange for a payment to the participant with respect to each share subject to the cancelled award of an amount equal to the excess of the consideration to be paid per share of common stock in the change in control transaction over the exercise price per share, if any, under the award.

The 2021 Plan will continue in effect until it is terminated by our compensation committee, provided, however, that all awards will be granted, if at all, within ten years of its effective date. The compensation committee may amend, suspend or terminate the 2021 Plan at any time, provided that without stockholder approval, the plan cannot be amended to increase the number of shares authorized, change the class of persons eligible to receive incentive stock options, or effect any other change that would require stockholder approval under any applicable law or listing rule.

Our 2014 Stock Option Plan (the “2014 Plan”), was originally adopted by our board of directors and approved by our stockholders in June 2014. As of December 31, 2021,2022, we had options to purchase 9,138,4137,659,369 shares of common stock outstanding under our 2014 Plan. In connection with the closing of our IPO, our board of directors terminated the 2014 Plan and will not grant any further awards under such plan, but the 2014 Plan will continue to govern outstanding awards granted thereunder. Our compensation committee administers the 2014 Plan and has the authority, among other things, to construe and interpret the terms of the 2014 Plan and awards granted thereunder.

Our 2000 Stock Option Plan (the “2000 Plan”), expired in 2010 but continues to govern outstanding awards granted thereunder. As of December 31, 2021,2022, we had options to purchase 141,04957,549 shares of common stock outstanding under our 2000 Plan. Our compensation committee administers our 2000 Plan and has the authority, among other things, to construe and interpret the terms of our 2000 Plan and awards granted thereunder.

We maintain a retirement savings plan (“401(k) Plan”), for the benefit of our eligible employees, including our named executive officers. Our 401(k) Plan is intended to qualify under Sections 401 of the Internal Revenue Code. Each participant in the 401(k) Plan may contribute up to the statutory limit of his or her pre-tax compensation. In addition, we can make discretionary matching contributions. All salary deferrals, rollovers and matching contributions are 100% vested when contributed. The 401(k) Plan provides for automatic salary deferrals of 3% of compensation with a 1% escalator each year. Participants are permitted to waive the automatic deferral provision.

Notwithstanding the appointment of KPMG LLP, and even if our stockholders ratify their appointment, our audit committee, in its discretion, may appoint another independent registered public accounting firm at any time during our fiscal year if our audit committee believes that such a change would be in the best interests of our Company and our stockholders. At the Annual Meeting, our stockholders are being asked to ratify the appointment of KPMG LLP as our independent registered public accounting firm for our fiscal year ending December 31, 2021.2023. Our board of directors is submitting the appointment of KPMG LLP to our stockholders because we value our stockholders' views on our independent registered public accounting firm and as a matter of good corporate governance. If our stockholders do not ratify the appointment of KPMG LLP, our audit committee may reconsider the appointment or may continue to retain KPMG LLP for 2021.2023. Representatives of KPMG LLP are expected to be present at the Annual Meeting, and they will have an opportunity to make a statement and are expected to be available to respond to appropriate questions from our stockholders.

The following table summarizes the fees of KPMG LLP, our independent registered public accounting firm, billed to us in each of the last two fiscal years for audit services and billed to us in each of the last two fiscal years for other services:

Our audit committee generally pre-approves all audit and non-audit services prior to such services being performed by the independent registered public accounting firm. Before engaging an independent registered public accountant firm to render audit or non-audit services, the engagement is approved by our audit committee or the engagement to render services is entered into pursuant to pre-approval policies and procedures established by the audit committee.

The audit committee reviewed and discussed with management and our independent registered public accounting firm, KPMG LLP, the audited financial statements included in our Annual Report on Form 10-K for the year ended December 31, 2021.2022. In addition, the audit committee has discussed with KPMG LLP those matters required to be discussed by the applicable requirements of the Public Company Accounting Oversight Board (the “PCAOB”) and the SEC.

The audit committee has also received and reviewed the written disclosures and the letter from KPMG LLP required by the applicable requirements of the PCAOB regarding KPMG LLP’s communications with the audit committee concerning independence, and has discussed with KPMG LLP its independence from us and our management.

Respectfully submitted by the audit committee,

Barry Zwarenstein (Chair)

Our board of directors has adopted a written related person transaction policy setting forth the policies and procedures for the review and approval or ratification of related person transactions. This policy covers, with certain exceptions set forth in Item 404 of Regulation S-K under the Securities Act, any transaction, arrangement or relationship, or any series of similar transactions, arrangements or relationships in which we were or are to be a participant, where the amount involved exceeds $120,000 and a related person had or will have a direct or indirect material interest, including, without limitation, purchases of goods or services by or from the related person or entities in which the related person has a material interest, indebtedness, guarantees of indebtedness and employment by us of a related person. In reviewing and approving any such transactions, our audit committee is tasked to consider all relevant facts and circumstances, including, but not limited to, whether the transaction is on terms comparable to those that could be obtained in an arm’s length transaction with an unrelated third party and the extent of the related person’s interest in the transaction.

InfoHorizon, LLC provides information technology software development to us. Nitin Jain, the brother-in-law of our executive officer Jayesh Sahasi, is the chief executive officer of InfoHorizon, LLC. For the years ended December 31, 2022, 2021 2020 and 2019,2020, we recorded $3.0 million, $2.5 million $1.7 million and $1.5$1.7 million, respectively, in research and development expense on in our consolidated statement of operations.

Eric Federman, the son of our director Irwin Federman, is one of our employees.was employed by us in 2022. His annual base salary isin 2022 was $160,000 and he iswas eligible to participate in our equity incentive and other employee benefit plans and programs. Eric Federman’s employment with us ended in March 2023.

We have entered into indemnification agreements with each of our directors and executive officers. These agreements, among other things, require us to indemnify each director and executive officer to the fullest extent permitted by Delaware law, including indemnification of expenses such as attorneys’ fees, judgments, penalties fines and settlement amounts incurred by the director or executive officer in any action or proceeding, including any action or proceeding by or in right of us, arising out of the person’s services as a director or executive officer.

Beneficial ownership is determined in accordance with the rules of the SEC and generally includes voting or investment power with respect to securities. Common stock issuable upon the exercise, conversion or settlement of options, warrants, restricted stock units or other rights to acquire common stock that are currently exercisable, convertible or subject to settlement, or exercisable, convertible or subject to settlement within 60 days of February 28, 20222023 are deemed to be outstanding and beneficially owned by the holder for the purpose of computing share and percentage ownership of that holder, but are not treated as outstanding for the purpose of computing the percentage ownership of any other person. Except as indicated in the footnotes to the table below, and subject to community property laws where applicable, we believe the persons and entities named in the table below have sole voting and investment power with respect to all common stock shown as beneficially owned by them. Unless otherwise indicated, the address of each of the individuals and entities named below is c/o ON24, Inc., 50 Beale Street, 8th Floor, San Francisco, California 94015. The percentage of shares beneficially owned is computed on the basis of 47,544,80447,155,902 shares of common stock outstanding as of February 28, 2022.2023.

Section 16(a) of the Exchange Act requires our executive officers, directors and persons who own more than ten percent of a registered class of our equity securities to file reports of ownership and changes in ownership with the SEC. Executive officers, directors and greater than ten-percent stockholders are required by SEC regulation to furnish us with copies of all Section 16(a) forms they file.

Based solely on our review of the copies of such forms furnished to us and the written representations from certain of the reporting persons that no other reports were required during the fiscal year ended December 31, 2021,2022, all executive officers, directors and greater than ten-percent beneficial owners complied with the reporting requirements of Section 16(a).

Stockholders who intend to have a proposal considered for inclusion in our proxy materials for presentation at our 20232024 Annual Meeting of Stockholders (the “2023“2024 Annual Meeting”) pursuant to Rule 14a-8 under the Exchange Act must submit the proposal to our Secretary at our offices at 50 Beale Street, 8th Floor, San Francisco, California 94015 not later than December 29, 2022.30, 2023.

Stockholders intending to present a proposal at the 20232024 Annual Meeting, but not to include the proposal in our proxy statement, or to nominate a person for election as a director, must comply with the requirements set forth in our Bylaws. Our Bylaws require, among other things, that our Secretary receive written notice from the stockholder of record of their intent to present such proposal or nomination not less than 90 days nor more than 120 days prior to the first anniversary of the preceding year’s annual meeting. Therefore, we must receive notice of such a proposal or nomination for the 20232024 Annual Meeting no earlier than the close of business on February 10, 202324, 2024 and no later than the close of business on March 12, 2023.25, 2024. The notice must contain the information required by the Bylaws, a copy of which is available upon request to our Secretary as well as on EDGAR. In the event that the date of our 20222023 Annual Meeting of Stockholders is more than 30 days before or more than 6030 days after June 10, 2022,

cases notwithstanding the stockholder's compliance with this deadline. We reserve the right to reject, rule out of order, or take other appropriate action with respect to any proposal that does not comply with these or other applicable requirements.

The SEC has adopted rules that permit companies and brokers to satisfy the delivery requirements for proxy statements and annual reports with respect to two or more stockholders sharing the same address by delivering a single proxy statement addressed to those stockholders. This process, which is commonly referred to as “householding,” potentially means extra convenience for stockholders and cost savings for companies.

As of the date of this proxy statement, the board of directors knows of no business, other than that described in this proxy statement, that will be presented for consideration at the 20222023 Annual Meeting. If any other business comes before the 20222023 Annual Meeting or any adjournment or postponement thereof, proxy holders may vote their respective proxies at their discretion.

By Order of the Board of Directors

William Weesner

San Francisco