Purpose of the Annual Meeting

        At the Annual Meeting, our stockholders will vote to elect six directors to hold office for a one-year term expiring at the Annual Meeting of Stockholders to be held in 2021, or until a successor is elected and qualified, will vote on an advisory, non-binding basis, on the Company's executive compensation program, and will vote to ratify the appointment of Moss Adams LLP as our independent registered public accounting firm for the fiscal year ending December 31, 2020. In addition, management will report on our performance over the last fiscal year and, following the Annual Meeting, respond to questions from stockholders.

Materials provided

        The Board is sending you this Proxy Statement and the enclosed proxy card in order to solicit your proxy to vote your shares at the Annual Meeting. As a stockholder, you are invited to attend the meeting and are entitled to vote on the items of business described in this Proxy Statement.

Annual Meeting attendance

        All stockholders as of March 20, 2020 (the "Record Date"), or their duly appointed proxies, may attend the Annual Meeting. You may need to bring personal identification. Gaining admission to the Annual Meeting depends on how your stock ownership is recorded with our transfer agent, Continental Stock Transfer & Trust Company (the "Transfer Agent"). If your stock is held in the name of a bank,

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broker or other holder of record and you plan to attend the Annual Meeting, please obtain proof of ownership, such as a current brokerage account statement or certification from your broker. If your stock is registered directly in your name with our Transfer Agent, all you need is proof of identity; no proof of ownership is needed.

Voting at the Annual Meeting

        Holders of our common stock ("Common Stock") as of the close of business on the Record Date will be entitled to vote at the Annual Meeting. On the Record Date, there were 48,254,575 shares of Common Stock outstanding, each of which is entitled to one vote with respect to each matter to be voted on at the Annual Meeting. There is no stockholder statutory right of appraisal or dissent with respect to any matters to be voted on at the Annual Meeting.

Quorum requirement

        The presence at the Annual Meeting, in person or by proxy, of the holders of a majority of the voting power of all outstanding shares of Common Stock entitled to vote shall constitute a quorum for the transaction of business. Proxies marked as abstaining (including proxies containing broker non-votes) on any matter to be acted upon by stockholders will be treated as present at the meeting for purposes of determining a quorum.

Stockholder of record & beneficial owner

        All stockholders are invited to attend the Annual Meeting. All shares that have been properly voted and not revoked will be voted at the Annual Meeting. Most of our stockholders hold their shares through a stockbroker, bank or other nominee rather than directly in their own name. As summarized below, there are distinctions between shares held of record and those owned beneficially.

Stockholder of Record

        If your shares are registered directly in your name with the Transfer Agent, you are considered the stockholder of record, and these proxy materials are being sent directly to you by us. As the stockholder of record, you have the right to grant your voting proxy directly to us or to vote in person at the Annual Meeting. We have enclosed a proxy card for you to use.

Voting in person at the Annual Meeting—You may vote in person at the Annual Meeting. If you choose to do so, please bring the enclosed proxy card and proof of identification. Even if you plan to attend the Annual Meeting, we recommend that you vote your shares in advance as described below so that your vote will be counted if you later decide not to attend the Annual Meeting.

Voting without attending the Annual Meeting—Please complete and properly sign and date the accompanying proxy card and return it to the Transfer Agent in the accompanying pre-addressed envelope.

Changing your vote after returning your proxy card—You can revoke your proxy before it is exercised at the meeting by:

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delivering written notice of revocation of the proxy to our Secretary prior to the Annual Meeting;



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executing and delivering a later dated proxy card to our Secretary; or



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attending and voting by ballot in person at the Annual Meeting.

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Beneficial Owner of Shares

        If your shares are held in a stock brokerage account, by a bank or other nominee, you are considered the beneficial owner of shares held in "street name" and these proxy materials are being forwarded to you by your broker, bank or nominee who is considered, with respect to your shares, the stockholder of record. As the beneficial owner, you have the right to direct the stockholder of record how to vote your shares. Your broker, bank or nominee has enclosed a voting instruction card for your use.

Voting without attending the Annual Meeting—Please follow the instructions provided by your broker, bank or nominee. You may vote by mail by completing, signing and dating the voting instruction card provided by your broker, bank or nominee and mailing the card to such entities in the accompanying pre-addressed envelopes.

Changing your vote after returning your proxy card—You may submit new voting instructions by contacting your broker, bank or other nominee. You may also vote at the Annual Meeting in person by following the instructions in the next section below.

Voting in person at the Annual Meeting—You may vote in person at the Annual Meeting by obtaining a signed "legal proxy" from the record holder (e.g., your broker, bank or nominee) prior to the meeting. Please bring your signed "legal proxy" and proof of identification to the meeting.

Required votes to approve each item

        Each outstanding share of Common Stock is entitled to one vote on each proposal at the Annual Meeting. All matters require the existence of a quorum at the Annual Meeting. All proposals require an affirmative vote of the majority of shares represented in person or by proxy, other than the election of Directors, which is determined by plurality voting. The individual receiving the largest number of votes for each position will be elected.

        In voting on Proposal 1, the election of Directors, you may vote "FOR" the nominee or your vote may be "WITHHELD" with respect to the nominee. In voting on any other proposal, you may vote "FOR", "AGAINST", or "ABSTAIN" with respect to the proposal. A properly executed proxy marked "ABSTAIN" with respect to any other proposal will not be voted, although it will be counted for purposes of determining whether there is a quorum. An abstention on any other proposal will have the effect of a negative vote on that matter. If you are a beneficial owner, shares represented by broker non-votes (when the broker indicates they do not have their customer's direction on how to vote, nor has discretionary authority on how to vote) will be counted in determining whether there is a quorum but will not be counted as votes cast on any proposal where the broker indicated they do not have discretionary voting authority.

Inspector of elections

        Our Executive Vice President, Chief Legal Officer and Secretary, John M. Perisich, will act as Inspector of Elections and oversee the voting results. The Inspector of Elections will also determine the presence of a quorum.

Voting results of the Annual Meeting

        We will announce preliminary voting results at the Annual Meeting and will publish final results in a Current Report on a Form 8-K filing with the Securities and Exchange Commission ("SEC") within four business days of the Annual Meeting.

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Board recommendations

        The Board recommends a vote:

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FOR Proposal No. 1 to elect each of the six director nominees to hold office for a one-year term expiring at the Annual Meeting of Stockholders to be held in 2021 or until a successor is elected and qualified.



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FOR Proposal No. 2, the non-binding, advisory vote approving the Company's executive compensation program.



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FOR Proposal No. 3 to ratify the appointment of Moss Adams LLP as our independent registered public accounting firm for the fiscal year ending December 31, 2020.

        Unless you give other instructions on your proxy card, the individual(s) named as proxy holder on the proxy card will vote in accordance with the recommendations of the Board.

Expense of soliciting proxies

        We will pay the costs for the solicitation of proxies, including the cost of preparing and mailing this Proxy Statement. Proxies are being solicited primarily by mail, but the solicitation by mail may be followed-up by solicitation in person, or by telephone or facsimile, by our regular employees without additional compensation for such proxy solicitation activity or by a proxy solicitation firm. We will reimburse brokers, banks and other custodians and nominees for their reasonable out-of-pocket expenses incurred in sending proxy materials to our stockholders.

Information about Primoris Services Corporation

        We maintain a corporate website atwww.prim.com. Visitors to the Investor Relations section of our website can view and print copies of our SEC filings, including this Proxy Statement and Forms 10-K, 10-Q and 8-K. Copies of the charters for our Audit Committee, Compensation Committee and Nominating and Corporate Governance Committee and our Code of Conduct, as well as our Sustainability Report are also available through our website. Alternatively, stockholders may obtain, without charge, copies of all of these documents by writing to Investor Relations at the Company's headquarters. Please note that the information contained on our website is not incorporated by reference in, nor considered to be a part of, this Proxy Statement.

Documents not incorporated by reference

        The Audit Committee Report and the Compensation Committee Report are not deemed filed with the SEC and shall not be deemed incorporated by reference into any prior or future filings made by us under the Securities Act of 1933, as amended (the "Securities Act"), or the Exchange Act, except to the extent that we specifically, and in writing, incorporate such information by reference.

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MATTERS TO COME BEFORE THE MEETING
PROPOSAL 1—– ELECTION OF DIRECTORS​