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As filed with the Securities and Exchange Commission on April 8, 2004

Registration No. 333-113639

UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

AMENDMENT NO. 1

TO

FORM S-4

REGISTRATION STATEMENT

Under

The Securities Act of 1933

HUNTINGTON BANCSHARES INCORPORATED

(Exact Name of Registrant as Specified in its Charter)

Huntington Bancshares Incorporated

Huntington Center

41 South High Street

Columbus, Ohio 43287

(614) 480-8300

(Address, including Zip Code, and Telephone Number, including Area Code, of Registrant’s Principal Executive Offices)

Richard A. Cheap, Esq.

General Counsel and Secretary

Huntington Bancshares Incorporated

41 South High Street

Columbus, Ohio 43287

(614) 480-8300

(Name, Address, including Zip Code, and Telephone Number, including Area Code, of Agent for Service)

With copies to:

Approximate date of commencement of the proposed sale of the securities to the public: As soon as practicable after this Registration Statement becomes effective and upon completion of the merger described in the enclosed proxy statement/prospectus.

If the securities being registered on this Form are being offered in connection with the formation of a holding company and there is compliance with General Instruction G, check the following box. ¨

If this Form is filed to register additional securities for an offering pursuant to Rule 462(b) under the Securities Act of 1933, check the following box and list the Securities Act registration statement number of the earlier effective registration statement for the same offering. ¨

If this Form is a post-effective amendment filed pursuant to Rule 462(d) under the Securities Act, check the following box and list the Securities Act registration statement number of the earlier effective registration statement for the same offering. ¨

The Registrant hereby amends this Registration Statement on such date or dates as may be necessary to delay its effective date until the Registrant shall file a further amendment which specifically states that this Registration Statement shall thereafter become effective in accordance with section 8(a) of the Securities Act of 1933 or until the registration statement shall become effective on such dates as the Commission, acting pursuant to said section 8(a), may determine.

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Information contained herein is subject to completion or amendment. A registration statement relating to these securities has been filed with the Securities and Exchange Commission. These securities may not be sold nor may offers to buy be accepted prior to the time the registration statement becomes effective. This proxy statement/prospectus shall not constitute an offer to sell or the solicitation of any offer to buy nor shall there be any sale of these securities in any jurisdiction in which such offer, solicitation or sale would be unlawful prior to registration or qualification under the securities laws of any such jurisdiction.

MERGER PROPOSED—YOUR VOTE IS VERY IMPORTANT

Dear Stockholder:

The board of directors of Unizan Financial Corp. has unanimously approved a strategic merger of Unizan into Huntington Bancshares Incorporated.

If the merger is completed, you will receive 1.1424 shares of Huntington common stock for each share of Unizan common stock you hold immediately prior to the merger. The following table shows the closing sale prices of Huntington common stock and Unizan common stock as reported on the Nasdaq National Market on January 26, 2004, the last trading day before we announced the merger, and on April 7, 2004, the last practicable trading day before the distribution of this proxy statement/prospectus. This table also shows the implied value of the merger consideration proposed for each share of Unizan common stock, which we calculated by multiplying the closing price of Huntington common stock on those dates by 1.1424, the exchange ratio. Huntington and Unizan common stock are each quoted on the Nasdaq National Market under the symbols “HBAN” and “UNIZ,” respectively.

We expect that the merger will generally be tax free to you, except with respect to any cash received by you instead of receiving any fractional share of Huntington common stock.

We cannot complete the merger unless it is approved by the holders of at least two-thirds of all outstanding shares of Unizan common stock. Unizan will hold a special stockholders’ meeting to vote on this merger proposal. Your vote is important. Whether or not you plan to attend the special stockholders’ meeting, please take the time to vote your shares in accordance with the instructions contained in this document. If you do not vote, it will have the same effect as voting against the merger.

The Unizan board of directors unanimously recommends that you

vote FOR approval of the merger agreement.

This document describes the special meeting, the merger, the documents related to the merger and other related matters. Please carefully read this entire document. You also can obtain information about our company and Huntington from documents that we and Huntington have filed with the Securities and Exchange Commission.

Neither the Securities and Exchange Commission nor any state securities commission has approved or disapproved the Huntington common stock to be issued under this joint proxy statement/prospectus or determined if this joint proxy statement/prospectus is accurate or adequate.

Any representation to the contrary is a criminal offense.

The date of this proxy statement/prospectus is April 8, 2004, and it is first being mailed or otherwise delivered to Unizan stockholders on or about April 13, 2004.

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REFERENCES TO ADDITIONAL INFORMATION

This document incorporates important business and financial information about Huntington and Unizan from documents that are not included in or delivered with this document. You can obtain documents incorporated by reference in this document by requesting them in writing or by telephone from the appropriate company at the following addresses:

You will not be charged for any of these documents that you request. Unizan stockholders requesting documents should do so by May 18, 2004 in order to receive them before the special meeting.

See “Where You Can Find More Information” on page 64.

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UNIZAN FINANCIAL CORP.

220 Market Avenue South

Canton, Ohio 44702

NOTICE OF SPECIAL MEETING OF STOCKHOLDERS

Unizan Financial Corp. will hold a special meeting of stockholders at the Marriott McKinley Grand Hotel, 320 Market Avenue South, Canton, Ohio, at 10:00 a.m., local time, on May 25, 2004 to consider and vote upon the following matters:

The Unizan board of directors has fixed the close of business on April 6, 2004 as the record date for the Unizan special meeting. Only Unizan stockholders of record at that time are entitled to notice of, and to vote at, the Unizan special meeting, or any adjournment or postponement of the Unizan special meeting. A complete list of Unizan stockholders entitled to vote at the special meeting will be made available for inspection by any Unizan stockholder at the time and place of the Unizan special meeting. In order for the merger agreement to be approved, the holders of two-thirds of the Unizan shares outstanding and entitled to vote thereon must vote in favor of adoption of the merger agreement.

Whether or not you plan to attend the special meeting, please submit your proxy with voting instructions. Please vote as soon as possible by accessing the Internet site listed on the Unizan proxy card, by calling the toll-free number listed on the Unizan proxy card, or by submitting your proxy card by mail. To submit your proxy by mail, please complete, sign, date and return the accompanying proxy card in the enclosed self-addressed, stamped envelope. This will not prevent you from voting in person, but it will help to secure a quorum and avoid added solicitation costs. Any holder of Unizan common stock who is present at the Unizan special meeting may vote in person instead of by proxy, thereby canceling any previous proxy. In any event, a proxy may be revoked in writing at any time before the Unizan special meeting in the manner described in the accompanying proxy statement/prospectus.

The Unizan board of directors has unanimously approved the merger agreement and unanimously recommends that Unizan stockholders vote “FOR” adoption of the merger agreement.

BY ORDER OF THE BOARD OF DIRECTORS,

April 8, 2004

YOUR VOTE IS IMPORTANT. PLEASE COMPLETE, SIGN, DATE AND RETURN YOUR PROXY CARD, WHETHER OR NOT YOU PLAN TO ATTEND THE SPECIAL MEETING.

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QUESTIONS AND ANSWERS ABOUT VOTING PROCEDURES FOR THE

UNIZAN SPECIAL MEETING

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Any stockholder entitled to vote at the Unizan special meeting may vote in person whether or not a proxy has been previously given, but the mere presence (without notifying Mr. Mann and voting) of a stockholder at the special meeting will not constitute revocation of a previously given proxy.

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SUMMARY

This summary highlights selected information from this document. It does not contain all of the information that is important to you. We urge you to carefully read the entire document and the other documents to which we refer in order to fully understand the merger and the related transactions. See “Where You Can Find More Information” on page 64. Each item in this summary refers to the page of this document on which that subject is discussed in more detail.

In the Merger Unizan Stockholders Will Receive 1.1424 Shares of Huntington Common Stock per Share of Unizan Common Stock (page 29)

We are proposing the merger of Unizan with and into Huntington. If the merger is completed, each Unizan stockholder will receive 1.1424 shares of Huntington common stock for each share of Unizan common stock held immediately prior to the merger. We refer to this 1.1424-to-1 ratio as the exchange ratio. Huntington will not issue any fractional shares of Huntington common stock in the merger. Unizan stockholders who would otherwise be entitled to a fractional share of Huntington common stock will instead receive an amount in cash based on the average of the closing sale prices of Huntington common stock on the five full trading days immediately prior to the date on which the merger is completed.

Example: If you hold 100 shares of Unizan common stock, you will receive 114 shares of Huntington common stock and a cash payment instead of the 0.24 of a share of Huntington common stock that you otherwise would have received (i.e., 100 shares x 1.1424 = 114.24 shares). If the five day average price was $21.83, the cash payment would be equal to $5.24 (i.e., 0.24 shares x $21.83 = $5.24).

Tax-Free Transaction to Unizan Stockholders (page 43)

The merger has been structured to qualify as a reorganization for U.S. federal income tax purposes. In addition, it is a condition to our respective obligations to complete the merger that Huntington receives the opinion of Wachtell, Lipton, Rosen & Katz, and Unizan receives the opinion of Black, McCuskey, Souers & Arbaugh, in each case, that the merger qualifies as a reorganization for U.S. federal income tax purposes. Accordingly, holders of Unizan stock generally will not recognize any gain or loss for U.S. federal income tax purposes on the exchange of their Unizan stock for Huntington stock in the merger, except for any gain or loss that may result from the receipt of cash instead of a fractional share of Huntington common stock.

The federal income tax consequences described above may not apply to all holders of Unizan stock. Your tax consequences will depend on your individual situation. Accordingly, we strongly urge you to consult your tax advisor for a full understanding of the particular tax consequences of the merger to you.

Comparative Market Prices and Share Information (page 63)

Huntington common stock is quoted on the Nasdaq National Market under the symbol “HBAN.” Unizan common stock is quoted on the Nasdaq National Market under the symbol “UNIZ.” The following table shows the closing sale prices of Huntington common stock and Unizan common stock as reported on the Nasdaq National Market on January 26, 2004, the last trading day before we announced the merger, and on April 7, 2004, the last practicable trading day before the distribution of this document. This table also shows the implied value of the merger consideration proposed for each share of Unizan common stock, which we calculated by multiplying the closing price of Huntington common stock on those dates by 1.1424, the exchange ratio.

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The market price of Huntington common stock and Unizan common stock will fluctuate prior to the merger. You should obtain current market quotations for the shares.

Unizan’s Financial Advisor Provided a Financial Opinion Letter to the Unizan Board of Directors (page 21)

In deciding to approve the merger, the Unizan board of directors considered the opinion its financial advisor, Sandler O’Neill & Partners, L.P., provided to the Unizan board of directors on January 27, 2004, that as of that date, and based on and subject to the considerations in its opinion, the exchange ratio in the merger agreement was fair from a financial point of view to holders of Unizan common stock. Sandler O’Neill has confirmed its opinion as of the date of this document. A copy of the opinion is attached to this document as Appendix B. Unizan stockholders should read the opinion completely and carefully to understand the assumptions made, matters considered and limitations of the review undertaken by Sandler O’Neill in providing its opinion. Unizan agreed to pay Sandler O’Neill a transaction fee in connection with the merger which, based upon the closing price of Huntington’s common stock on April 6, 2004, would be approximately $3.6 million. The principal portion of such fee is payable upon completion of the merger. The Sandler O’Neill opinion is not a recommendation as to how any stockholder of Unizan should vote with respect to the merger or any other matter.

Huntington’s Dividend Policy (page 31)

During 2003, Huntington declared cash dividends totaling $0.67 per share. Huntington’s most recent quarterly cash dividend was $0.175 per share. The Huntington board of directors can change its dividend at any time, and considers the appropriate level of dividends after taking into account its financial condition and level of net income, its future prospects, economic conditions, industry practices and other factors, including applicable banking laws and regulations. Huntington does not have any present intention to reduce its regular quarterly cash dividend.

Our Reasons for the Merger (pages 18 and 20)

Our companies are proposing to merge for a number of reasons, including because:

The Unizan Board of Directors Unanimously Recommends that Unizan Stockholders Vote “FOR” Adoption of the Merger Agreement (page 18)

The Unizan board of directors believes that the merger is in the best interests of Unizan and its stockholders and has unanimously approved the merger agreement. The Unizan board of directors unanimously recommends that Unizan stockholders vote “FOR” adoption of the merger agreement.

Unizan’s Directors and Officers Have Financial Interests in the Merger That Differ From Your Interests (page 34)

Unizan’s executive officers and directors have economic interests in the merger that are different from, or in addition to, their interests as Unizan stockholders. These interests include the right of certain executive officers to receive severance payments and extended insurance benefits under the terms of existing severance and salary continuation agreements and the acceleration of vesting of stock options as a result of the merger.

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Information about the Companies (page 15)

Huntington Bancshares Incorporated

Huntington is a multi-state diversified financial holding company organized under Maryland law in 1966 and headquartered in Columbus, Ohio. Through its subsidiaries, Huntington is engaged in providing full-service commercial and consumer banking services, mortgage banking services, automobile financing, equipment leasing, investment management, trust services, and discount brokerage services, as well as underwriting credit life and disability insurance, and selling other insurance and financial products and services. The Huntington National Bank, organized in 1866, is Huntington’s only bank subsidiary. At December 31, 2003, Huntington Bank had 162 banking offices in Ohio, 114 banking offices in Michigan, 25 banking offices in West Virginia, 22 banking offices in Indiana, 12 banking offices in Kentucky, 3 private banking offices in Florida, and one foreign office in each of the Cayman Islands and Hong Kong. Selected financial services, including those of Huntington’s mortgage group, are also conducted in other states including Arizona, Florida, Georgia, Maryland, New Jersey, Pennsylvania, and Tennessee. Foreign banking activities, in total or with any individual country, are not significant to the operations of Huntington. At December 31, 2003, Huntington and its subsidiaries had 7,983 full-time equivalent employees.

Unizan Financial Corp.

Unizan Financial Corp. is a financial holding company organized under the laws of the State of Ohio and is headquartered in Canton, Ohio. Unizan conducts a full-service commercial and retail banking business through its wholly-owned subsidiary, Unizan Bank, National Association. Unizan Financial Corp. was formed as a result of the merger between BancFirst Ohio Corp. and UNB Corp. that was completed on March 7, 2002.

Conditions That Must Be Satisfied or Waived for the Merger to Occur (page 36)

Currently, we expect to complete the merger promptly following the end of the second quarter of 2004. However, as more fully described in this document and in the merger agreement, the completion of the merger depends on a number of conditions being satisfied or, where legally permissible, waived. These conditions include, among others, approval by the stockholders of Unizan, the receipt of all required regulatory approvals, such as approval by the Board of Governors of the Federal Reserve System and the Office of the Comptroller of the Currency, and the receipt of legal opinions by each company regarding the tax treatment of the merger.

We cannot be certain when, or if, the conditions to the merger will be satisfied or waived, or that the merger will be completed.

Termination of the Merger Agreement (page 41)

We may agree to terminate the merger agreement before completing the merger, even after stockholder approval, as long as the termination is approved by each of our boards of directors.

In addition, either of us may decide to terminate the merger agreement, even after stockholder approval, if certain conditions have not been met, such as obtaining the necessary regulatory approvals or the other company’s material breach of its representations, warranties or covenants. Either of us may terminate the merger agreement if the merger has not been completed by January 27, 2005, unless the reason the merger has not been completed by that date is a breach of the merger agreement by the company seeking to terminate the merger agreement or if Unizan does not obtain the approval of its stockholders.

Huntington may terminate the merger agreement if, among other things, Unizan withdraws or qualifies its recommendation or it recommends or endorses an alternative transaction. Unizan may terminate the merger

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agreement if the Huntington share price declines to below $18.48 and the decline is at least 15% greater than the decline of the S&P Bank Index, in each case measured over a five day trading period before the last regulatory approval is obtained.

Board of Directors and Management of Huntington following Completion of the Merger (page 29)

After the merger, the board of directors of the combined company will have a total of 12 members, including one director from Unizan’s current board of directors appointed by Huntington and reasonably acceptable to Unizan.

The Rights of Unizan Stockholders will be Governed by Maryland Law and by the Huntington Governing Documents after the Merger (page 45)

The rights of Unizan stockholders will change as a result of the merger due to differences in Huntington’s and Unizan’s governing documents and due to the fact that the companies are incorporated in different states (Unizan in Ohio and Huntington in Maryland). This document contains descriptions of stockholder rights under each of the Huntington and Unizan governing documents and applicable state law, and describes the material differences between them.

Regulatory Approvals Required for the Merger (page 32)

We have agreed to use our reasonable best efforts to obtain all regulatory approvals required to complete the transactions contemplated by the merger agreement. These approvals include approval from the Federal Reserve Board and various federal and state regulatory authorities. Huntington and Unizan have completed, or will complete, the filing of applications and notifications to obtain the required regulatory approvals.

Although we do not know of any reason why we cannot obtain these regulatory approvals in a timely manner, we cannot be certain when or if we will obtain them.

Unizan will Hold its Special Meeting on May 25, 2004 (page 12)

The Unizan special meeting will be held on May 25, 2004, at 10:00 a.m., local time, at the Marriott McKinley Grand Hotel, 320 Market Avenue South, Canton, Ohio. At the Unizan special meeting, Unizan stockholders will be asked to:

Record Date. Only holders of record at the close of business on April 6, 2004 will be entitled to vote at the Unizan special meeting. Each share of Unizan common stock is entitled to one vote. As of the record date of April 6, 2004, there were 21,711,707 shares of Unizan common stock entitled to vote at the Unizan special meeting.

Required Vote. To approve the merger agreement, the holders of two-thirds of the voting power of Unizan common stock entitled to vote must vote in favor of approving the merger agreement. Because approval is based on the affirmative vote of two-thirds of shares outstanding, a Unizan stockholder’s failure to vote, a broker non-vote or an abstention will have the same effect as a vote against the merger.

As of the Unizan record date, directors and executive officers of Unizan and their affiliates had the right to vote 1,583,849 shares of Unizan common stock, or approximately 7.3% of the outstanding Unizan common stock entitled to be voted at the Unizan special meeting. At that date, directors and executive officers of Huntington and their affiliates had the right to vote approximately 7,200 shares of Unizan common stock entitled to be voted at the Unizan special meeting, or less than one percent of the outstanding Unizan common stock.

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Dissenter’s Rights (page 31)

If a Unizan stockholder delivers a written demand for payment of the fair cash value of his shares of Unizan common stock not later than ten days after the special meeting, he will be entitled, if and when the merger is completed, to receive the fair cash value of his shares of Unizan common stock. The stockholder’s right to receive the fair cash value of his Unizan common stock, however, is contingent upon his strict compliance with the procedures set forth in 1701.85 of the Ohio General Corporation Law, a copy of which is attached to this document as Annex C. If a Unizan stockholder wishes to submit a written demand for payment of the fair cash value of his shares of Unizan common stock, he must deliver his demand no later than June 4, 2004 to Roger L. Mann, President and Chief Executive Officer of Unizan, 220 Market Avenue South, Canton, Ohio 44702.

Comparative Market Prices and Dividends (page 63)

Huntington common stock and Unizan common stock are quoted on the Nasdaq National Market. The following table sets forth the high and low closing prices of shares of Huntington common stock and Unizan common stock as reported on the Nasdaq National Market, and the quarterly cash dividends declared per share for the periods indicated.

Unizan stockholders are advised to obtain current market quotations for Huntington common stock and Unizan common stock. The market price of Huntington common stock and Unizan common stock will fluctuate between the date of this proxy statement/prospectus and the completion of the merger. No assurance can be given concerning the market price of Huntington common stock before or after the effective date of the merger.

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SELECTED CONSOLIDATED HISTORICAL FINANCIAL DATA OF HUNTINGTON

Set forth below are highlights from Huntington’s consolidated financial data as of and for the years ended December 31, 2003 through 1999. You should read this information in conjunction with Huntington’s consolidated financial statements and related notes included in Huntington’s Annual Report on Form 10-K for the year ended December 31, 2003, which are incorporated by reference in this document and from which this information is derived. See “Where You Can Find More Information” on page 64.

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SELECTED CONSOLIDATED HISTORICAL FINANCIAL DATA OF UNIZAN

Set forth below are highlights from Unizan’s consolidated financial data as of and for the years ended December 31, 2003 through 1999. You should read this information in conjunction with Unizan’s consolidated financial statements and related notes included in Unizan’s Annual Report on Form 10-K for the year ended December 31, 2003, which are incorporated by reference in this document and from which this information is derived. See “Where You Can Find More Information” on page 64.

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COMPARATIVE PER SHARE DATA

The following table sets forth for Huntington common stock and Unizan common stock certain historical, pro forma and pro forma-equivalent per share financial information. The pro forma and pro forma-equivalent per share information gives effect to the merger as if the merger had been effective on the date and period presented. The information included under “Per Equivalent Unizan Share” was obtained by multiplying the “Pro Forma Combined” amounts by the 1.1424 exchange ratio. The pro forma data in the tables assume that the merger is accounted for using the purchase method of accounting. See “Accounting Treatment” on page 43.

We expect that we will incur merger and integration costs as a result of combining our companies. We have estimated those costs will approximate $26 million before taxes. We also anticipate that the merger will provide the combined company with financial benefits that include reduced operating expenses. We have estimated those benefits will include a reduction of operating expenses of approximately $17 million before taxes. The anticipated benefits from the merger, the expected amount of the merger costs and the timing of their recognition and realization may be revised as additional information becomes available and additional analysis is performed. While helpful in illustrating the financial characteristics of the combined company under one set of assumptions, the pro forma information does not reflect these anticipated financial benefits and, accordingly, does not attempt to predict or suggest future results. It also does not necessarily reflect what the historical results of the combined company would have been had our companies been combined. These costs and benefits are not reflected in the pro forma data.

The information in the following table is based on, and should be read together with, the historical financial information that we have presented in our prior filings with the Securities and Exchange Commission and the pro forma financial information that appears elsewhere in this document. See “Where You Can Find More Information” on page 64. Upon completion of the merger, the operating results of Unizan will be reflected in the consolidated financial statements of Huntington on a prospective basis.

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CAUTIONARY STATEMENT REGARDING FORWARD-LOOKING STATEMENTS

This document contains or incorporates by reference a number of forward-looking statements regarding the financial condition, results of operations, earnings outlook, business and prospects of Huntington, Unizan and the potential combined company and may include statements for the period following the completion of the merger. You can find many of these statements by looking for words such as “plan,” “believe,” “expect,” “intend,” “anticipate,” “estimate,” “project,” “potential,” “possible” or other similar expressions.

The forward-looking statements involve certain risks and uncertainties. The ability of either Huntington or Unizan to predict results or the actual effects of its plans and strategies, or those of the combined company, is inherently uncertain. Accordingly, actual results may differ materially from anticipated results. Some of the factors that may cause actual results or earnings to differ materially from those contemplated by the forward-looking statements include, but are not limited to, the following:

Because these forward-looking statements are subject to assumptions and uncertainties, actual results may differ materially from those expressed or implied by these forward-looking statements. Unizan stockholders are cautioned not to place undue reliance on these statements, which speak only as of the date of this document or the date of any document incorporated by reference in this document. For additional information about factors that could cause actual results to differ materially from those expressed or implied by the forward-looking statements, please see the reports that Huntington and Unizan have filed with the SEC as described under “Where You Can Find More Information” beginning on page 64.

All subsequent written and oral forward-looking statements concerning the merger or other matters addressed in this document and attributable to Huntington or Unizan or any person acting on their behalf are expressly qualified in their entirety by the cautionary statements contained or referred to in this section. Except to the extent required by applicable law or regulation, Huntington and Unizan undertake no obligation to update these forward-looking statements to reflect events or circumstances after the date of this document or to reflect the occurrence of unanticipated events.

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THE UNIZAN SPECIAL MEETING

This section contains information from Unizan for Unizan stockholders about the special meeting of Unizan stockholders that has been called to consider and adopt the merger agreement.

Together with this document, we are also sending you a notice of the Unizan special meeting and a form of proxy that is solicited by the Unizan board of directors. The Unizan special meeting will be held on May 25, 2004 at 10:00 a.m., local time, at the Marriott McKinley Grand Hotel, 320 Market Avenue South, Canton, Ohio.

Matters to Be Considered

The purpose of the Unizan special meeting is to vote on a proposal for adoption of the merger agreement.

You also will be asked to vote upon a proposal to approve the adjournment of the special meeting, if necessary, to solicit additional proxies, in the event that there are not sufficient votes at the time of the special meeting to adopt the merger agreement.

Proxies

Each copy of this document mailed to Unizan stockholders is accompanied by a form of proxy with instructions for voting by mail, by telephone or through the Internet. If voting by mail, you should complete and return the proxy card accompanying this document to ensure that your vote is counted at the Unizan special meeting, or at any adjournment or postponement of the Unizan special meeting, regardless of whether you plan to attend the Unizan special meeting. You may also vote your shares by telephone or through the Internet. Information and applicable deadlines for voting by telephone or through the Internet are set forth in the enclosed proxy card instructions.

You may revoke your signed proxy card at any time before it is voted by signing and returning a proxy card with a later date, delivering a written revocation letter to Unizan’s Secretary, or by attending the Unizan special meeting in person, notifying the Secretary, and voting by ballot at the Unizan special meeting. If you have voted your shares by telephone or through the Internet, you may revoke your prior telephone or Internet vote by recording a different vote, or by signing and returning a proxy card dated as of a date that is later than your last telephone or Internet vote.

Any stockholder entitled to vote in person at the Unizan special meeting may vote in person whether or not a proxy has been previously given, but the mere presence (without notifying the Secretary) of a stockholder at the Unizan special meeting will not constitute revocation of a previously given proxy.

Written notices of revocation and other communications about revoking your proxy should be addressed to:

Unizan Financial Corp.

220 Market Avenue South

Canton, Ohio 44702

Attention:  Roger L. Mann

President and Chief Executive Officer

If your shares are held in street name by a broker, bank or other nominee, you should follow the instructions of your broker, bank or other nominee regarding the revocation of proxies.

All shares represented by valid proxies that we receive through this solicitation, and that are not revoked, will be voted in accordance with your instructions on the proxy card. If you make no specification on your proxy card as to how you want your shares voted before signing and returning it, your proxy will be voted “FOR” approval of the merger agreement and “FOR” approval of the proposal to adjourn the special meeting, if necessary, to solicit additional proxies in the event that there are not sufficient votes at the time of the special meeting to approve the merger agreement. According to the Unizan code of regulation, business to be conducted

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at a special meeting of stockholders may only be brought before the meeting pursuant to Unizan’s notice of meeting. Accordingly, no matters other than the matters described in this proxy statement/prospectus will be presented for action at the Unizan special meeting or at any adjournment or postponement of the Unizan special meeting.

Unizan stockholders should NOT send Unizan stock certificates with their proxy cards. Following completion of the merger, Unizan stockholders will be mailed a transmittal form with instructions on how to exchange their Unizan stock certificates for Huntington stock certificates and cash instead of fractional shares, if applicable.

Solicitation of Proxies

Unizan will bear the entire cost of soliciting proxies from you. In addition to solicitation of proxies by mail, we will request that banks, brokers, and other record holders send proxies and proxy material to the beneficial owners of Unizan common stock and secure their voting instructions, if necessary. We will reimburse the record holders for their reasonable expenses in taking those actions. We have also made arrangements with Morrow & Co., Inc. to assist us in soliciting proxies and have agreed to pay them $7,500 plus reasonable expenses for these services. If necessary, we may use several of our regular employees, who will not be specially compensated, to solicit proxies from Unizan stockholders, either personally or by telephone, facsimile, letter or other electronic means.

Householding

Unless it has received contrary instructions, Unizan may send a single copy of this proxy statement/prospectus to any household at which two or more Unizan stockholders reside if Unizan believes the stockholders are members of the same family. Each stockholder in the household will continue to receive a separate proxy card. This process, known as “householding,” reduces the volume of duplicate information received at your household and helps to reduce Unizan’s expenses.

If you would like to receive your own proxy statement/prospectus, follow the instructions described below. Similarly, if you share an address with another stockholder and together both of you would like to receive only a single proxy statement/prospectus, follow these instructions:

If your shares are registered in your own name, please contact Unizan’s transfer agent, Unizan Bank, National Association, and inform them of your request by calling them at (330) 438-1206 or writing to them at 624 Market Avenue North, Canton, Ohio 44702.

If a bank, broker or other nominee holds your shares, please contact your bank, broker or other nominee directly.

Record Date

The Unizan board of directors has fixed the close of business on April 6, 2004 as the record date for determining the Unizan stockholders entitled to receive notice of and to vote at the Unizan special meeting. At that time, 21,711,707 shares of Unizan common stock were outstanding.

Voting Rights and Vote Required

The presence, in person or by properly executed proxy, of the holders of a majority of the outstanding shares of Unizan common stock is necessary to constitute a quorum at the Unizan special meeting. Abstentions and broker non-votes will be counted for the purpose of determining whether a quorum is present. When we refer to broker non-votes, we are referring to unvoted proxies submitted by brokers, who are not able to vote on the merger agreement absent instructions from the applicable beneficial owner.

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Approval of the merger agreement requires the affirmative vote of the holders of two-thirds of the voting power of Unizan common stock entitled to vote at the Unizan special meeting. You are entitled to one vote for each share of Unizan common stock you held as of the record date.

Because the affirmative vote of the holders of two-thirds of the voting power of Unizan common stock entitled to vote at the Unizan special meeting is needed for us to proceed with the merger, the failure to vote by proxy or in person will have the same effect as a vote against the merger. Abstentions and broker non-votes also will have the same effect as a vote against the merger. Accordingly, the Unizan board of directors urges Unizan stockholders to complete, date, and sign the accompanying proxy card and return it promptly in the enclosed postage-paid envelope if voting by mail, call the toll-free number listed in the proxy card instructions if voting by telephone, or access the Internet site listed in the proxy card instructions if voting through the Internet.

As of the record date directors and executive officers of Unizan and their affiliates had the right to vote 1,583,849 shares of Unizan common stock, or approximately 7.3% of the outstanding Unizan common stock at that date.

Recommendation of the Unizan Board of Directors

The Unizan board of directors has unanimously approved the merger agreement and the transactions it contemplates. The Unizan board of directors determined that the merger agreement and the transactions it contemplates are advisable and in the best interests of Unizan and its stockholders and unanimously recommends that you vote “FOR” adoption of the merger agreement. See “The Merger-Unizan’s Reasons for the Merger; Recommendation of Unizan’s Board of Directors” on page 18 for a more detailed discussion of the Unizan board of directors’ recommendation.

Attending the Meeting

All Unizan stockholders, including stockholders of record and stockholders who hold their shares through banks, brokers, nominees or any other holder of record, are invited to attend the Unizan special meeting. Stockholders of record can vote in person at the special meeting. If you are not a stockholder of record, you must obtain a proxy executed in your favor, from the record holder of your shares, such as a broker, bank or other nominee, to be able to vote in person at the special meeting. If you plan to attend the special meeting, you must hold your shares in your own name or have a letter from the record holder of your shares confirming your ownership and you must bring a form of personal photo identification with you in order to be admitted. We reserve the right to refuse admittance to anyone without proper proof of share ownership and without proper photo identification.

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INFORMATION ABOUT THE COMPANIES

Huntington Bancshares Incorporated

Huntington Bancshares Incorporated is a multi-state diversified financial holding company organized under Maryland law in 1966 and headquartered in Columbus, Ohio. Through its subsidiaries, Huntington is engaged in providing full-service commercial and consumer banking services, mortgage banking services, automobile financing, equipment leasing, investment management, trust services, and discount brokerage services, as well as underwriting credit life and disability insurance, and selling other insurance and financial products and services. The Huntington National Bank, organized in 1866, is Huntington’s only bank subsidiary. At December 31, 2003, Huntington Bank had 162 banking offices in Ohio, 114 banking offices in Michigan, 25 banking offices in West Virginia, 22 banking offices in Indiana, 12 banking offices in Kentucky, 3 private banking offices in Florida, and one foreign office in each of the Cayman Islands and Hong Kong. Selected financial services, including those of Huntington’s mortgage group, are also conducted in other states including Arizona, Florida, Georgia, Maryland, New Jersey, Pennsylvania, and Tennessee. Foreign banking activities, in total or with any individual country, are not significant to the operations of Huntington. At December 31, 2003, Huntington and its subsidiaries had 7,983 full-time equivalent employees.

Additional information about Huntington and its subsidiaries is included in documents incorporated by reference in this proxy statement/prospectus. See “Where You Can Find More Information” on page 64.

Unizan Financial Corp.

Unizan Financial Corp. is a financial holding company organized under the laws of the State of Ohio and is headquartered in Canton, Ohio. It conducts a full-service commercial and retail banking business through its wholly-owned subsidiary, Unizan Bank, National Association. Unizan Financial Corp. was formed as a result of the merger between BancFirst Ohio Corp. and UNB Corp. that was completed on March 7, 2002.

Unizan Financial Corp.’s main affiliate, Unizan Bank, National Association, is a full-service banking organization with 45 banking offices offering a wide range of commercial, retail and fiduciary banking services primarily to customers in Stark, Summit, Wayne, Muskingum, Licking, Franklin, Greene, Miami and Montgomery Counties of Ohio. The Aircraft Finance Group of the Bank maintains a local sales office in Franklin County as well as two regional offices in Sacramento, California and Orlando, Florida, which generate loans nationally. Also, the Bank has small business lending centers to serve small businesses and specializes in loans guaranteed by the U.S. Department of Commerce, Small Business Administration. Currently, small business lending centers are located in Cleveland, Columbus, Cincinnati and Dayton, Ohio; Indianapolis, Indiana, Mt. Arlington, New Jersey, and Detroit, Michigan.

The Bank offers a broad range of loan, deposit, trust and miscellaneous products and services. Loan products include commercial and commercial real estate loans, government guaranteed loans, a variety of residential mortgage and construction loan products, direct and indirect consumer installment loans, home equity lines of credit, aircraft financing, VISA business lines of credit and accounts receivable financing. Deposit products include interest and non-interest bearing checking products, various savings and money market products, and certificates of deposit and IRAs with various maturities.

Additional information about Unizan and its subsidiaries is included in documents incorporated by reference in this proxy statement/prospectus. See “Where You Can Find More Information” on page 64.

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