SECURITIES AND EXCHANGE COMMISSION

Washington D.C., 20549

FORM 11-K

FOR THE FISCAL YEAR ENDED DECEMBER 31, 2003

OR

FOR THE TRANSITION PERIOD FROM              TO             .

COMMISSION FILE NO. 0-2525

A. Full Title of the Plan and the address of the Plan, if different from that of the issuer named below:

Huntington Investment and Tax Savings Plan

B. Name of issuer of the securities held pursuant to the Plan and the address of its principal executive office:

Huntington Bancshares Incorporated

Huntington Center

41 South High Street

Columbus, Ohio 43287

HUNTINGTON INVESTMENT AND TAX SAVINGS PLAN

REQUIRED INFORMATION

Item 4. Financial Statements and Supplemental Schedule for the Plan.

The Huntington Investment and Tax Savings Plan (the “Plan”) is subject to the Employee Retirement Income Security Act of 1974 (“ERISA”). In lieu of the requirements of Items 1-3 of this Form, the Plan is filing financial statements and a supplemental schedule prepared in accordance with the financial reporting requirements of ERISA. The Plan financial statements and supplemental schedule for the fiscal year ended December 31, 2003, are included as Exhibit 99.1 to this report on Form 11-K and are incorporated herein by reference. The Plan financial statements and supplemental schedule have been audited by Ernst & Young LLP, Independent Registered Public Accounting Firm, and their report is included therein.

EXHIBITS

SIGNATURES

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

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