Exhibit 99.1

Huntington Investment and Tax Savings Plan

Employer ID No.: 31-0724920

Plan Number: 002

Financial Statements as of and for the Years Ended DECEMBER 31, 2013 AND 2012, Supplemental Schedule as of December 31, 2013, and

Reports of Independent Registered Public Accounting Firms

HUNTINGTON INVESTMENT AND TAX SAVINGS PLAN

TABLE OF CONTENTS

REPORT OF INDEPENDENT REGISTERED PUBLIC ACCOUNTING FIRM

To the Compensation Committee of the Board of Directors of

Huntington Bancshares Incorporated and Plan Participants of the

Huntington Investment and Tax Savings Plan

Columbus, Ohio

We have audited the accompanying statement of net assets available for benefits of the Huntington Investment and Tax Savings Plan (the “Plan”) as of December 31, 2013, and the related statement of changes in net assets available for benefits for the year then ended. These financial statements are the responsibility of the Plan’s management. Our responsibility is to express an opinion on these financial statements based on our audit. The financial statements of the Plan as of and for the year ended December 31, 2012, were audited by other auditors whose report dated June 21, 2013 expressed an unqualified opinion on those financial statements.

We conducted our audit in accordance with standards of the Public Company Accounting Oversight Board (United States). Those standards require that we plan and perform the audit to obtain reasonable assurance about whether the financial statements are free of material misstatement. The Plan is not required to have, nor were we engaged to perform, an audit of its internal control over financial reporting. Our audit included consideration of internal control over financial reporting as a basis for designing audit procedures that are appropriate in the circumstances, but not for the purpose of expressing an opinion on the effectiveness of the Plan’s internal control over financial reporting. Accordingly, we express no such opinion. An audit includes examining, on a test basis, evidence supporting the amounts and disclosures in the financial statements. An audit also includes assessing the accounting principles used and significant estimates made by management, as well as evaluating the overall financial statement presentation. We believe that our audit provides a reasonable basis for our opinion.

In our opinion, the financial statements referred to above present fairly, in all material respects, the net assets available for benefits of the Plan as of December 31, 2013, and the changes in net assets available for benefits for the year then ended, in conformity with accounting principles generally accepted in the United States of America.

Our audit was performed for the purpose of forming an opinion on the basic financial statements taken as a whole. The accompanying supplemental Schedule of Assets (Held at End of Year) as of December 31, 2013 is presented for the purpose of additional analysis and is not a required part of the basic financial statements but is supplementary information required by the Department of Labor’s Rules and Regulations for Reporting and Disclosure under the Employee Retirement Income Security Act of 1974. The supplemental schedule is the responsibility of the Plan’s management. The supplemental schedule has been subjected to the auditing procedures applied in the audit of the basic financial statements and, in our opinion, is fairly stated in all material respects in relation to the basic financial statements taken as a whole.

/s/ Ary Roepcke Mulchaey, P.C.

Columbus, Ohio

June 27, 2014

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REPORT OF INDEPENDENT REGISTERED PUBLIC ACCOUNTING FIRM

To the Compensation Committee of the Board of Directors of

Huntington Bancshares Incorporated and Plan Participants of the

Huntington Investment and Tax Savings Plan

Columbus, Ohio

We have audited the accompanying statement of net assets available for benefits of the Huntington Investment and Tax Savings Plan (the “Plan”) as of December 31, 2012, and the related statement of changes in net assets available for benefits for the year then ended. These financial statements are the responsibility of the Plan’s management. Our responsibility is to express an opinion on these financial statements based on our audit.

We conducted our audit in accordance with standards of the Public Company Accounting Oversight Board (United States). Those standards require that we plan and perform the audit to obtain reasonable assurance about whether the financial statements are free of material misstatement. The Plan is not required to have, nor were we engaged to perform, an audit of its internal control over financial reporting. Our audit included consideration of internal control over financial reporting as a basis for designing audit procedures that are appropriate in the circumstances, but not for the purpose of expressing an opinion on the effectiveness of the Plan’s internal control over financial reporting. Accordingly, we express no such opinion. An audit also includes examining, on a test basis, evidence supporting the amounts and disclosures in the financial statements, assessing the accounting principles used and significant estimates made by management, as well as evaluating the overall financial statement presentation. We believe that our audit provides a reasonable basis for our opinion.

In our opinion, such financial statements present fairly, in all material respects, the net assets available for benefits of the Plan as of December 31, 2012, and the changes in net assets available for benefits for the year then ended in conformity with accounting principles generally accepted in the United States of America.

/s/ Deloitte & Touche LLP

Columbus, Ohio

June 21, 2013

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HUNTINGTON INVESTMENT AND TAX SAVINGS PLAN

STATEMENTS OF NET ASSETS AVAILABLE FOR BENEFITS

DECEMBER 31, 2013 AND 2012

See notes to financial statements.

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HUNTINGTON INVESTMENT AND TAX SAVINGS PLAN

STATEMENTS OF CHANGES IN NET ASSETS AVAILABLE FOR BENEFITS

FOR THE YEARS ENDED DECEMBER 31, 2013 AND 2012

See notes to financial statements.

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HUNTINGTON INVESTMENT AND TAX SAVINGS PLAN

NOTES TO FINANCIAL STATEMENTS

AS OF AND FOR THE YEARS ENDED DECEMBER 31, 2013 AND 2012

The Huntington Investment and Tax Savings Plan (the “Plan”) is a defined contribution plan that was initially adopted by the Board of Directors (the “Board of Directors”) of Huntington Bancshares Incorporated (“Huntington”) on September 29, 1977, to be effective January 1, 1978, to provide benefits to eligible employees of Huntington, as defined in the Plan document. Plan participants should refer to the Plan document and summary plan description for a more complete description of the Plan’s provisions. On December 13, 2000, Huntington’s common stock held in accounts of participants who elected to have all or a portion of their accounts invested in Huntington’s common stock were designated an Employee Stock Ownership Plan (ESOP). The ESOP forms a portion of the Plan.

Amendments — From time to time, the Plan has been amended and restated. The most recent amendments to the Plan include provisions as necessary to conform to various legislation and guidance under the Internal Revenue Code (the “Code”), the provisions of the Employee Retirement Income Security Act of 1974 (ERISA), and employee eligibility requirements as well as matching provisions as further described in the Funding and Vesting section below.

Plan Termination — Pursuant to the Plan document, Huntington may terminate or modify the Plan at any time by resolution of its Board of Directors and subject to the provisions of ERISA and the Code.

Funding and Vesting — During 2012 eligible employees could enroll on the first day of the month following six months of employment and attainment of the age of 21. Beginning in 2013 eligible employees may enroll on their hire date. Participants may elect to make pre-tax and/or Roth 401(k) after tax contributions of up to 75% of their eligible compensation, up to certain statutory limits. During 2012 Huntington made a matching contribution equal to 100% on the first 3% and 50% on the next 2% of participant elective deferrals. Beginning in 2013 Huntington made a matching contribution equal to 100% on the first 4% of participant elective deferrals following six months of employment. Participant and employer contributions are fully vested at all times. See the Subsequent Events Note for plan amendments effective in 2014.

Administration — The Plan administrator is Huntington. Portions of Plan administration have been delegated by the Plan administrator to a committee of employees appointed by the Board of Directors of Huntington. The Plan administrator believes that the Plan is currently designed and operated in compliance with the applicable requirements of the Code and the provisions of ERISA, as amended.

Participant Accounts — Each participant’s account is credited with the participant’s own contribution and an allocation of Huntington’s contribution, as applicable, and Plan earnings. Investment income or loss is allocated to participant accounts based on proportional account balances in their respective investments. The benefit to which a participant is entitled is the benefit that can be provided from the participant’s individual account.

Fees and Expenses — Certain administrative fees are paid from the general assets of Huntington and are excluded from these financial statements. Participants are also charged a fixed amount for administration of the Plan. Investment related expenses are included in the net appreciation of fair value of investments. Fees incurred by the Plan for investment management services or recordkeeping are also included in the net appreciation in fair value of investments because they are paid through a revenue sharing arrangement rather than a direct payment from the Plan.

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Investment Options — Plan participants are permitted to direct their deferrals and employer matching contributions to any combination of investment options, including the Huntington Conservative Deposit Account, Huntington common stock and a variety of investment funds. Huntington has the sole discretion to determine or change the number and nature of investment options in the Plan. An active participant may change or suspend deferrals pursuant to the terms set forth in the Plan document. If a Plan participant enrolls without making an investment election, all contributions will be allocated to the Huntington Conservative Deposit Account.

Plan Investments — Plan investments consist of interest bearing cash, shares of Huntington common stock and mutual funds. The investments are held by the trust division of The Huntington National Bank (the “Plan Trustee”), a wholly owned subsidiary of Huntington. The Plan Trustee purchases and sells shares of Huntington common stock on the open market at market prices. Additionally, the Plan Trustee may directly purchase from, and sell to, Huntington, at market prices, shares of Huntington common stock. The Plan Trustee purchases and redeems shares of mutual funds in accordance with rules of the mutual funds.

Participant Loans — The Plan does not permit participant loans. However, as a result of acquisitions, certain participant loans were rolled over into the Plan. Participant loans are recorded at unpaid principal balance plus any accrued but unpaid interest, at rates commensurate with prevailing rates at the time funds were borrowed. The amount recorded approximates current value. Principal and interest is paid ratably through payroll deductions. Participant loans are listed as notes receivable from participants in the Plan’s financial statements.

Contributions — Employee and employer contributions to participants’ accounts in the Plan are invested pursuant to the participants’ investment direction elections on file.

Benefit Distributions and Other Withdrawals — A participant may request that the portion of his or her account that is invested in Huntington common stock be distributed in shares of Huntington common stock with cash paid in lieu of any fractional shares. All other distributions from the Plan are paid in cash.

Distributions and withdrawals are reported at fair value and recorded by the Plan when payments are made.

Participants are permitted to take distributions and withdrawals from their accounts in the Plan under the circumstances set forth in the Plan document. Generally, participants may request withdrawal of funds in their account attributable to: (i) rollover contributions; (ii) after-tax contributions; and (iii) pre-April 1, 1998, Employer contributions. Employee pre-tax elective deferrals and post April 1, 1998 employer matching contributions are subject to special withdrawal rules and generally may not be withdrawn from the Plan prior to a participant’s death, disability, termination of employment, or attainment of age 59 1/2. Certain distributions of employee deferrals may be made, however, in the event a participant requests a distribution due to financial hardship as defined by the Plan. Participants should refer to the summary plan description for a complete summary of the Plan provisions. Participants may withdraw up to 100% of their account balances in the Plan for any reason after they have reached age 59 1/2.

Plan participants have the option of reinvesting cash dividends paid on Huntington common stock or having dividends paid in cash.

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Basis of Presentation — The financial statements of the Plan are presented on the accrual basis and are prepared in accordance with accounting principles generally accepted in the United States of America (GAAP).

In conjunction with applicable accounting standards, all material subsequent events have been either recognized in the financial statements or disclosed in the notes to financial statements.

Dividends and Interest Income — Dividends are recognized as of their ex-dividend date. Interest is recorded on an accrual basis when earned.

Fair Value Measurements — Accounting Standards Codification (ASC) Topic 820 defines fair value as the exchange price that would be received for an asset or paid to transfer a liability (an exit price) in the principal or most advantageous market for the asset or liability in an orderly transaction between market participants on the measurement date. ASC 820 also establishes a three-level valuation hierarchy for disclosure of fair value measurements. The valuation hierarchy is based upon the transparency of inputs to the valuation of an asset or liability as of the measurement date. The three levels are defined as follows:

Level 1 — inputs to the valuation methodology are quoted prices (unadjusted) for identical assets or liabilities in active markets.

Level 2 — inputs to the valuation methodology include quoted prices for similar assets and liabilities in active markets, and inputs that are observable for the asset or liability, either directly or indirectly, for substantially the full term of the financial instrument.

Level 3 — inputs to the valuation methodology are unobservable and significant to the fair value measurement.

A financial instrument’s categorization within the valuation hierarchy is based upon the lowest level of input that is significant to the fair value measurement. The Plan’s policy is to recognize significant transfers between levels at the beginning of the reporting period.

Use of Estimates — The preparation of financial statements in conformity with GAAP requires management to make estimates and assumptions that affect amounts of assets and liabilities, and changes therein, reported in the financial statements. Actual results could differ from those estimates.

Risks and Uncertainties — The Plan utilizes various investment instruments, including mutual funds and common stock. In general, investment securities are exposed to various risks such as interest rate, credit, and overall market volatility. Due to the level of risk associated with certain investment securities, it is reasonably possible that changes in the values of investment securities will occur in the near term and that such changes will materially affect the amounts in the financial statements.

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The following individual investments represent 5% or more of the fair value of net assets available for benefits as of December 31:

The Plan’s investments (including investments purchased, sold, and held during the year) appreciated in carrying value for the years ended December 31 as follows:

Certain plan investments are held with the Huntington National Bank or are shares of mutual funds managed by Huntington Asset Advisors, Inc., a subsidiary of the Huntington National Bank. These investments are held by the Plan Trustee, and therefore, qualify as party-in-interest investments.

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The following table lists the fair value of party-in-interest investments at December 31:

Costs and expenses paid by the Plan for administration totaled $330,234 and $309,969 for 2013 and 2012, respectively. Amounts are included in benefit distributions and other withdrawals in the Plan financial statements.

The Plan obtained its latest determination letter dated September 24, 2013, in which the Internal Revenue Service (IRS) stated the Plan, as then designed, was qualified under Section 401(a) of the Code and, therefore, the related trust is exempt from taxation. Subsequent to this determination by the IRS, the Plan was amended and restated. Once qualified, the Plan is required to operate in conformity with the Code to maintain its qualification. Huntington believes the Plan is being operated in compliance with applicable requirements of the Code and related state statutes, and that the trust, which forms a part of the Plan, is qualified and exempt from federal income and state franchise taxes.

GAAP requires the evaluation of tax positions taken by the Plan and recognition of a tax liability if the Plan has taken an uncertain tax position that is not more likely than not to be sustained upon examination by the IRS. Huntington, on behalf of the Plan, has analyzed the tax positions taken by the Plan, and has concluded that as of December 31, 2013 and 2012, there are no uncertain tax positions taken or expected to be taken that would require recognition of a liability or disclosure in the financial statements. The Plan is subject to routine audits; however, there are currently no audits for any tax periods in progress. The Plan administrator believes it is no longer subject to income tax examinations for years prior to 2010.

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Investments of the Plan are accounted for at cost on the trade-date and are reported at fair value. Interest bearing cash accounts have a fair value equal to the amount payable on demand. Huntington common stock is valued using the year-end closing price as determined by the National Association of Securities Dealers Automated Quotations. Mutual funds are valued at quoted market prices that represent the net asset value of shares held by the Plan at year-end. There have been no changes in the valuation methodologies used at December 31, 2013 and 2012. The following tables set forth by level within the fair value hierarchy a summary of the Plan’s investments measured at fair value on a recurring basis at December 31, 2013 and 2012. For the years ended December 31, 2013 and 2012, there were no significant transfers in or out of Levels 1, 2, or 3.

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There were no amounts included in net assets available for benefits allocated to individuals who have withdrawn from the Plan at December 31, 2013 and 2012.

The following Plan amendments went into effect on January 1, 2014. The Plan was amended and restated to require all new employees hired as of January 1, 2014 to complete one month of service before they can enroll in the Plan. Any employees who meet the eligibility requirements after January 1, 2014 will be automatically enrolled in the Plan unless they opt out. Employer contributions start with the first employee deferral. Employer contributions for employees hired after January 1, 2014 will be on a two-year cliff-vesting schedule. After two years of service the employer matching contribution will be 100% vested. An annual discretionary profit sharing contribution was also established. The profit sharing contributions are on a three-year cliff-vesting schedule, so that after three years of service these contributions are 100% vested.

Effective March 1, 2014 the plan sponsor acquired Camco Financial. Camco employees were able to enroll in the Plan effective March 1, 2014 and were auto-enrolled effective April 1, 2014, excluding employees who opted out of the Plan.

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SUPPLEMENTAL SCHEDULE

HUNTINGTON INVESTMENT AND TAX SAVINGS PLAN

EIN: 31-0724920 Plan Number: 002

SCHEDULE H, PART IV, LINE 4I — SCHEDULE OF ASSETS (HELD AT END OF YEAR)

AS OF DECEMBER 31, 2013

See notes to financial statements

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