Additional Proxy Soliciting Materials (Form DEFA14A)

UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

SCHEDULE 14A

(Rule 14a-101)

INFORMATION REQUIRED IN PROXY STATEMENT

SCHEDULE 14A INFORMATION

Proxy Statement Pursuant to Section 14(a) of the Securities

Exchange Act of 1934 (Amendment No. ___)

þ			Filed by the Registrant			o			Filed by a Party other than the Registrant

Check the appropriate box:
o			Preliminary Proxy Statement
o			CONFIDENTIAL, FOR USE OF THE COMMISSION ONLY (AS PERMITTED BY RULE 14a-6(e)(2))
o			Definitive Proxy Statement
þ			Definitive Additional Materials
o			Soliciting Material under §240.14a-12

INSIGHT ENTERPRISES, INC.

(Name of Registrant as Specified in its Charter)

(Name of Person(s) Filing Proxy Statement, if other than the Registrant)

Payment of Filing Fee (Check all boxes that apply):
þ			No fee required.
o			Fee paid previously with preliminary materials.
o			Fee computed on table in exhibit required by Item 25(b) per Exchange Act Rules 14a-6(i)(1) and 0-11.

Insight Enterprises, Inc.

supplement to the definitive proxy statement

for the 2026 annual meeting of stockholders

to be held on Wednesday, May 13, 2026

This proxy statement supplement (the "Supplement") supplements and amends the definitive proxy statement on Schedule 14A (the "Proxy Statement") filed with the Securities and Exchange Commission by Insight Enterprises, Inc. (the "Company") on April 2, 2026.

Following the filing of the Proxy Statement, it was determined that the number of common stock outstanding and entitled to vote at the Annual Meeting included in the "Frequently Asked Questions Concerning the Annual Meeting" section of the Proxy Statement inadvertently understated the number of outstanding shares by 283,621 shares due to an administrative error. The correct number of shares of common stock that were outstanding on the record date of March 16, 2026 and entitled to vote at the Annual Meeting is 30,361,891.

Except as specifically discussed above, this Supplement does not otherwise modify or update any other disclosures presented in the Proxy Statement. This Supplement should be read with the Proxy Statement, and, from and after the date of this Supplement, any references to the "Proxy Statement" shall be deemed to include the Proxy Statement as amended by this Supplement.

If you have already voted by Internet, telephone, or by mail, you do not need to take any action unless you wish to change your vote. Proxy voting instructions already returned by stockholders (via Internet, telephone, or mail) will remain valid and will be voted at the Annual Meeting unless revoked. Important information regarding how to vote your shares and revoke proxies already cast is available in the Proxy Statement under the caption "Frequently Asked Questions Concerning the Annual Meeting."