Material Event (Form 8-K)

On August 17, 2026, Illumina, Inc. ("Illumina" or the "Company") completed a public offering of $300,000,000 aggregate principal amount of its 4.950% notes due 2029 (the "Notes").

Illumina expects to use the net proceeds from the offering, together with cash on hand, to repay its 4.650% notes due September 9, 2026, of which $500 million aggregate principal amount was outstanding as of June 28, 2026.

The Notes were issued pursuant to an Indenture (the "Indenture"), dated March 12, 2021, between the Company and U.S. Bank Trust Company, National Association, as successor in interest to U.S. Bank National Association, as trustee, and an officer's certificate establishing the terms of the Notes (which includes the form of Notes as an exhibit). The offering of the Notes was registered on a Registration Statement on Form S-3 (File No. 333-281921). The Notes will accrue interest at a rate of 4.950% per annum, payable semi-annually, and will mature on September 19, 2029.

Upon occurrence of an Event of Default (as defined in the Indenture) with respect to the Notes, the principal amount of the Notes may be declared, and/or become, due and payable immediately. The Company may, at its election, redeem the Notes, in whole or in part, from time to time at the redemption prices and on the terms and conditions set forth in the Notes.

The above description of the Notes is qualified in its entirety by reference to the Indenture, the officer's certificate and the form of the Notes filed as exhibits hereto, which exhibits are incorporated by reference herein.