ASGN Incorporated : 2023 Proxy

Proxy Statement

2 0 2 3 N O T I C E O F A N N U A L M E E T I N G O F S T O C K H O L D E R S

4400 Cox Road, Suite 110

Glen Allen, Virginia 23060

April 27, 2023

Dear Fellow Stockholder:

On behalf of your Board of Directors and management, you are cordially invited to attend the 2023 Annual Meeting of Stockholders (the "Annual Meeting") of ASGN Incorporated (the "Company" or "ASGN"), at which you will be asked to vote upon:

1. the election of Mark A. Frantz, Jonathan S. Holman and Arshad Matin, as directors for three-year terms to expire at our 2026 Annual Meeting of Stockholders;
2. an advisory vote to approve the Company's named executive officer compensation for the year ended December 31, 2022;
3. an advisory vote on the frequency of future advisory votes on executive compensation;
4. the ratification of the appointment of Deloitte & Touche LLP as our independent registered public accounting firm for the year ending December 31, 2023; and
5. such other business as may properly come before the Annual Meeting or any adjournments or postponements thereof.

The Annual Meeting will be held on Thursday, June 15, 2023, at 9:00 a.m. Eastern Time. The Annual Meeting will be held as a virtual meeting of stockholders, to be conducted exclusively online via live webcast. We believe that this virtual format prioritizes the health and well-being of our stockholders, and provides a format in which all of our stockholders have access to attend the meeting regardless of where they are located.

You will be able to participate in the Annual Meeting, submit questions during the Annual Meeting, and vote your shares electronically during the meeting by visiting www.meetnow.global/MGQ257C. Because the Annual Meeting is being conducted electronically, you will not be able to attend the meeting in person. Details regarding how to participate in the live webcast of the Annual Meeting and the business to be conducted at the meeting are provided in the accompanying Notice of Annual Meeting of Stockholders and Proxy Statement, which you are urged to read carefully.

Please promptly vote your shares by telephone, using the Internet, or by signing and returning your proxy in the enclosed envelope.

Your vote is important no matter how many shares you own. In order to ensure that your shares will be represented at the Annual Meeting, please vote your shares using one of the voting instruments available to you.

We thank you for your continued interest in ASGN and look forward to seeing you at the Annual Meeting.

Sincerely,

/s/ Theodore S. Hanson

Theodore S. Hanson

Chief Executive Officer

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4400 Cox Road, Suite 110

Glen Allen, Virginia 23060

NOTICE OF ANNUAL MEETING OF STOCKHOLDERS

to be held on Thursday, June 15, 2023

The 2023 Annual Meeting of Stockholders of ASGN Incorporated (the "Company" or "ASGN") will be held virtually and exclusively online via live webcast on Thursday, June 15, 2023, at 9:00 a.m. Eastern Time, for the purpose of considering and voting upon:

1. the election of Mark A. Frantz, Jonathan S. Holman and Arshad Matin, as directors for three-year terms to expire at our 2026 Annual Meeting of Stockholders;
2. an advisory vote to approve the Company's named executive officer compensation for the year ended December 31, 2022;
3. an advisory vote on the frequency of future advisory votes on executive compensation;
4. the ratification of the appointment of Deloitte & Touche LLP as our independent registered public accounting firm for the year ending December 31, 2023; and

5, such other business as may properly come before the Annual Meeting or any adjournments or postponements thereof.

The foregoing items of business are more fully described in the Proxy Statement accompanying this notice. The expenses of printing proxy materials, including expenses involved in forwarding materials to beneficial owners of stock, will be paid by ASGN Incorporated. Only stockholders of record at the close of business on April 19, 2023 are entitled to notice of, and to vote at, the Annual Meeting.

All stockholders are cordially invited to attend the live webcast of the Annual Meeting by visiting www.meetnow.global/MGQ257C. To participate in and vote at the Annual Meeting, stockholders will need the unique 15-digit control number (printed in the box marked by the arrow) in their Notice of Internet Availability of Proxy Materials or proxy card (if you request a printed copy of the proxy materials). However, to ensure your representation at the Annual Meeting, you may access your proxy card by going to www.envisionreports.com/ASGN, entering the information requested on your computer screen and following the simple instructions, or by calling (in the United States, U.S. territories, and Canada) toll free 1-800-652-VOTE (8683) on a touchtone telephone and following the simple instructions provided by the recorded message. The instructions for voting can be found with your proxy card, on the Notice, and on the website listed in the Notice. If you received or requested a printed version of the proxy card, you may also vote by mail. Any stockholder of record attending the Annual Meeting may vote during the Annual Meeting even if the stockholder has previously returned a proxy card. If you hold your shares in "street name," you must obtain a proxy in your name from your bank, broker or other holder of record in order to vote by ballot at the Annual Meeting.

By Order of the Board,

/s/ Jennifer Hankes Painter

Jennifer Hankes Painter

Secretary

April 27, 2023