UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

FORM 8-K

CURRENT REPORT

Pursuant to Section 13 or 15(d)

of the Securities Exchange Act of 1934

Date of Report (date of earliest event reported): March 27, 2017

Santander Holdings USA, Inc.

(Exact name of registrant as specified in its charter)

Registrant’s telephone number, including area code: (904) 357-9100

N/A

(Former name or former address, if changed since last report)

Check the appropriate box below if the Form 8-K filing is intended to simultaneously satisfy the filing obligation of the registrants under any of the following provisions (see General Instruction A.2. below):

On March 27, 2017 (the “Issue Date”), Santander Holdings USA, Inc. (“SHUSA”) completed its previously announced private placement of $1,000,000,000 aggregate principal amount of 3.700% senior unsecured notes due 2022 (the “Notes”). The Notes were issued pursuant to the Senior Debt Indenture, dated as of April 19, 2011 (the “Base Indenture”), by and between SHUSA and Deutsche Bank Trust Company Americas, as trustee (the “Trustee”), as amended by the Eighth Supplemental Indenture, dated as of March 1, 2017 (the “Eighth Supplemental Indenture”) and as supplemented by the Ninth Supplemental Indenture, dated as of March 27, 2017 (the “Ninth Supplemental Indenture”), in each case between SHUSA and the Trustee. The Notes were offered and sold only to qualified institutional buyers in the United States pursuant to Rule 144A and outside the United States pursuant to Regulation S under the Securities Act of 1933, as amended (the “Securities Act”). The Notes have not been registered under the Securities Act or any state securities laws and may not be offered or sold in the United States absent registration or an applicable exemption from the registration requirements of the Securities Act and applicable state laws. SHUSA intends to use the net proceeds from the sale of the Notes for general corporate purposes.

The Notes are SHUSA’s senior unsecured debt obligations and will rank equally with all SHUSA’s existing unsecured and unsubordinated obligations. Under the terms of the Ninth Supplemental Indenture, the Notes will mature on March 28, 2022 and will accrue interest at a rate equal to 3.700% per annum on the principal amount from the issue date, with such interest payable semi-annually in arrears on March 28 and September 28 each year, beginning on September 28, 2022.

The Indenture contains customary covenants (including covenants limiting SHUSA’s ability to create certain liens, enter into certain transactions, and consolidate or merge with, or convey, transfer or lease all or substantially all assets to, another person) and events of default (subject in certain cases to customary exceptions, as well as grace and cure periods).

The foregoing descriptions of the Base Indenture, the Eighth Supplemental Indenture and the Ninth Supplemental Indenture are qualified in its entirety by reference to the full text of the Base Indenture, the Eighth Supplemental Indenture and the Ninth Supplemental Indenture, respectively, which are filed as Exhibits 4.1, 4.2 and 4.3 hereto and incorporated by reference herein.

(d) Exhibits.

SIGNATURE

Pursuant to the requirements of the Securities Exchange Act of 1934, the registrant has duly caused this report to be signed on its behalf by the undersigned hereunto duly authorized.

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EXHIBIT INDEX

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