Alphabet files 424B2: prospectus (424B)

PROSPECTUS SUPPLEMENT (To Prospectus dated June 1, 2026)

6,000,000,000 Alphabet Inc.

We are offering 750,000,000 aggregate principal amount of our floating rate notes (the “floating rate notes”), 750,000,000 aggregate principal amount of our 3.700% notes due 2028 (the “2028 Notes”), 1,250,000,000 aggregate principal amount of our 4.050% notes due 2030 (the “2030 Notes”), 750,000,000 aggregate principal amount of our 4.250% notes due 2032 (the “2032 Notes”), 750,000,000 aggregate principal amount of our 4.500% notes due 2035 (the “2035 Notes”), 750,000,000 aggregate principal amount of our 4.875% notes due 2039 (the “2039

Notes”) and 1,000,000,000 aggregate principal amount of our 5.250% notes due 2045 (the “2045 Notes” and, together with the 2028 Notes, the 2030 Notes, the 2032 Notes, the 2035 Notes and the 2039 Notes, the “fixed rate notes”). The fixed rate notes and the floating rate notes are collectively referred to as the “notes.” The floating rate notes will mature on November 5, 2028, the 2028 Notes will mature on November 5, 2028, the 2030 Notes will mature on November 5, 2030, the 2032 Notes will mature on November 5, 2032, the 2035 Notes will mature on November 5, 2035, the 2039 Notes will mature on November 5, 2039 and the 2045 Notes will mature on November

5, 2045. Interest on the floating rate notes will accrue from November 5, 2026 and be payable quarterly in arrears on February 5, May 5, August 5 and November 5 of each year, beginning on February 5, 2027. The floating rate notes will bear interest at a floating rate equal to the Applicable EURIBOR Rate (as defined in “Description of the Notes—Information about EURIBOR”) based on the three-month EURIBOR, reset quarterly, plus 0.50% per annum. Interest on the fixed rate notes will accrue from November 5, 2026 and be payable on November 5 of each year, beginning on November 5, 2027. We may redeem any series of the fixed rate notes in whole or in part at any time or from time to time at the redemption prices described under the heading “Description of the Notes—Optional Redemption.” The floating rate notes will not be redeemable prior to maturity, except that we may redeem any series of the notes (including both the fixed rate notes and the floating rate notes) in whole, but not in part, at any time at our option in the event of certain changes in the tax laws of the United States that would require us to pay additional amounts as described under “Description of the

Notes—Redemption for Tax Reasons.”

The notes will be our senior unsecured obligations and will rank equally with our other unsecured and unsubordinated indebtedness from time to time outstanding. The notes will be structurally subordinated to all existing and future indebtedness and other obligations of our subsidiaries.

We intend to apply to list each series of the notes on the Nasdaq Bond Exchange (“Nasdaq”). The listing applications will be subject to approval by

Nasdaq. We currently expect trading in each series of the notes on Nasdaq to begin within 30 days after the original issue date. If such a listing is obtained, we have no obligation to maintain such listing and we may delist any series of the notes at any time. Currently, there is no public market for any series of the notes.

See “ Risk Factors ” beginning on page S-7 for a discussion of certain risks that should be considered in connection with an investment in the notes.

Neither the Securities and Exchange Commission (the “SEC”) nor

(1) Plus accrued interest, if any, from November 5, 2026, if settlement occurs after that date.

The summary below describes the principal terms of the notes. Certain of the terms described below are subject to important limitations and exceptions. The “Description of the Notes” section of this prospectus supplement and the “Description of Debt Securities” section of the accompanying prospectus contain a more detailed description of the terms of the notes. For purposes of this description, references to the “Company,” “we,” “our” and “us” refer only to Alphabet Inc. and not to its subsidiaries.

Issuer Alphabet Inc.

Notes Offered 750,000,000 aggregate principal amount of floating rate notes due 2028.

750,000,000 aggregate principal amount of 3.700% notes due 2028.

Maturity Dates The floating rate notes will mature on November 5, 2028.

The 2028 Notes will mature on November 5, 2028.

Interest Rates The floating rate notes will bear interest at a floating rate, reset quarterly, on each floating rate interest payment date (as defined in “Description of the Notes—Floating Rate Notes”), equal to the Applicable EURIBOR Rate based on the three-month EURIBOR plus 0.50% per annum.

The 2028 Notes will bear interest at a rate of 3.700% per year.

The 2030 Notes will bear interest at a rate of 4.050% per year.

The 2032 Notes will bear interest at a rate of 4.250% per year.

The 2035 Notes will bear interest at a rate of 4.500% per year.

The 2039 Notes will bear interest at a rate of 4.875% per year.

The 2045 Notes will bear interest at a rate of 5.250% per year.

Interest Payment Dates Interest will be payable quarterly in arrears for the floating rate notes on February 5, May 5, August 5 and November 5 of each year, beginning on February 5, 2027.

Interest will be payable annually in arrears for the fixed rate notes on November 5 of each year, beginning on November 5, 2027.

Currency of Payments Initial holders will be required to pay for the notes in euros, and all payments on the notes will be payable in euros; provided that if on or after the date of this prospectus supplement the euro is unavailable to us due to the imposition of exchange controls or other circumstances beyond our control or if the euro is no longer used by the then Member States of the European Monetary Union that have adopted the euro as their currency or for the settlement of transactions by public institutions of or within the international banking community, then all payments in respect of the notes will be made in U.S. dollars until the euro is again available to us or so used. The amount payable on any date in euros will be converted into U.S. dollars as described under “Description of the Notes—Issuance in Euros; Payment on the Notes.” Any payment in respect of the notes so made in U.S. dollars will not constitute an event of default under the notes or the indenture.

Optional Redemption We may redeem any series of the fixed rate notes in whole or in part at any time or from time to time at the applicable redemption prices.