Table of Contents

UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

FORM 10-Q

QUARTERLY REPORT PURSUANT TO SECTION 13 OR 15(d)

OF THE SECURITIES EXCHANGE ACT OF 1934

QUARTERLY PERIOD ENDED June 30, 2015

Commission File Number 1-34073

Huntington Bancshares Incorporated

41 South High Street, Columbus, Ohio 43287

Registrant’s telephone number (614) 480-8300

Indicate by check mark whether the Registrant (1) has filed all reports required to be filed by Section 13 or 15(d) of the Securities Exchange Act of 1934 during the preceding 12 months and (2) has been subject to such filing requirements for the past 90 days.     x  Yes    ¨  No

Indicate by check mark whether the registrant has submitted electronically and posted on its corporate Web site, if any, every Interactive Data File required to be submitted and posted pursuant to Rule 405 of Regulation S-T (§232.405 of this chapter) during the preceding 12 months (or for such shorter period that the registrant was required to submit and post such files).     x  Yes    ¨  No

Indicate by check mark whether the registrant is a large accelerated filer, an accelerated filer, a non-accelerated filer, or a smaller reporting company. See the definitions of “large accelerated filer,” “accelerated filer” and “smaller reporting company” in Rule 12b-2 of the Exchange Act. (Check one):

Indicate by check mark whether the registrant is a shell company (as defined in Rule 12b-2 of the Exchange Act).     ¨  Yes    x  No

There were 803,065,757 shares of Registrant’s common stock ($0.01 par value) outstanding on June 30, 2015.

Table of Contents

HUNTINGTON BANCSHARES INCORPORATED

INDEX

2

Table of Contents

Glossary of Acronyms and Terms

The following listing provides a comprehensive reference of common acronyms and terms used throughout the document:

3

Table of Contents

4

Table of Contents

5

Table of Contents

PART I. FINANCIAL INFORMATION

When we refer to “we”, “our”, and “us” in this report, we mean Huntington Bancshares Incorporated and our consolidated subsidiaries, unless the context indicates that we refer only to the parent company, Huntington Bancshares Incorporated. When we refer to the “Bank” in this report, we mean our only bank subsidiary, The Huntington National Bank, and its subsidiaries.

INTRODUCTION

We are a multi-state diversified regional bank holding company organized under Maryland law in 1966 and headquartered in Columbus, Ohio. Through the Bank, we have 149 years of servicing the financial needs of our customers. Through our subsidiaries, we provide full-service commercial and consumer banking services, mortgage banking services, automobile financing, equipment leasing, investment management, trust services, brokerage services, insurance service programs, and other financial products and services. Our 735 branches are located in Ohio, Michigan, Pennsylvania, Indiana, West Virginia, and Kentucky. Selected financial services and other activities are also conducted in various other states. International banking services are available through the headquarters office in Columbus, Ohio and a limited purpose office located in the Cayman Islands and another limited purpose office located in Hong Kong. Our foreign banking activities, in total or with any individual country, are not significant.

This MD&A provides information we believe necessary for understanding our financial condition, changes in financial condition, results of operations, and cash flows. The MD&A included in our 2014 Form 10-K should be read in conjunction with this MD&A as this discussion provides only material updates to the 2014 Form 10-K. This MD&A should also be read in conjunction with the Unaudited Condensed Consolidated Financial Statements, Notes to Unaudited Condensed Consolidated Financial Statements, and other information contained in this report.

Our discussion is divided into key segments:

A reading of each section is important to understand fully the nature of our financial performance and prospects.

6

Table of Contents

EXECUTIVE OVERVIEW

Summary of 2015 Second Quarter Results Compared to 2014 Second Quarter

For the quarter, we reported net income of $196.2 million, or $0.23 per common share, compared with $164.6 million, or $0.19 per common share, in the year-ago quarter (see Table 1).

Fully-taxable equivalent net interest income was $498.6 million, up $32.0 million, or 7%. The results reflected the benefit from a $5.5 billion, or 10%, increase in average earning assets, partially offset by an 8 basis point reduction in the net interest margin to 3.20%. Average earning asset growth included a $2.9 billion, or 6%, increase in average loans and leases, a $1.6 billion, or 14%, increase in average securities, and a $1.0 billion increase in average loans held-for-sale. The NIM contraction reflected an 8 basis point decrease related to the mix and yield of earning assets and a 2 basis point increase in funding costs, partially offset by a 2 basis point increase in the benefit from noninterest-bearing funds. While not affecting average balances, $0.8 billion of bank-level senior debt was issued at the end of the 2015 second quarter.

The provision for credit losses was $20.4 million, down $9.0 million, or 31%. NCOs were $25.4 million, down $3.3 million, or 11%. NCOs represented an annualized 0.21% of average loans and leases in the current quarter down from 0.25%. We remain pleased with the net charge-off performance across the entire portfolio. Consumer credit metrics continue to show an improving trend, while the commercial portfolios continue to experience some quarter-to-quarter volatility.

Noninterest income was $281.8 million, up $31.7 million, or 13%. The increase primarily reflected an increase in mortgage banking income of $15.8 million, or 70%, including an increase in origination and secondary marketing revenues, reflecting a higher gain on sale margin, and a net benefit from MSR hedging activities. In addition, other noninterest income increased $8.6 million, or 24%, primarily reflecting equipment operating lease income related to Macquarie Equipment Finance, which we have re-branded Huntington Technology Finance (HTF). Also, gain on sale of loans increased $8.5 million, or 218%, including the $5.3 million gain from the $0.8 billion automobile loan securitization and sale completed in the 2015 second quarter.

Noninterest expense was $491.8 million, up $33.1 million, or 7%. The increase primarily reflected an increase in personnel costs of $21.5 million, or 8%, reflecting the May implementation of annual merit increases, the addition of HTF employees, and an increase in benefits expense. In addition, other noninterest expense increased $7.8 million, or 23%, primarily reflecting operating lease expense related to HTF.

The tangible common equity to tangible assets ratio was 7.91% at June 30, 2015, down 47 basis points. On a Basel III transitional basis, the regulatory common equity tier 1 (CET1) risk-based capital ratio was 9.65% at June 30, 2015, and the regulatory tier 1 risk-based capital ratio was 10.41%. On a Basel I basis, the tier 1 common risk-based capital ratio was 10.26% at June 30, 2014, and the regulatory tier 1 risk-based capital ratio was 11.56%. All capital ratios were impacted by the repurchase of 22.8 million common shares over the last four quarters.

Business Overview

General

Our general business objectives are: (1) grow net interest income and fee income, (2) deliver positive operating leverage, (3) increase primary relationships across all business segments, (4) continue to strengthen risk management and reduce volatility, and (5) maintain strong capital and liquidity positions.

We reported good quarterly earnings that are increasingly being driven by our differentiated strategy and disciplined execution. Total revenue increased 9% year-over-year with net interest income and fee income contributing meaningfully to revenue performance. We received an immediate benefit to our earnings from HTF, while robust mortgage lending volume drove growth in mortgage banking income. Our capital markets and treasury management businesses, among others, also produced strong results.

The success we are seeing on the revenue front provides us the important opportunity to invest further in our business, though we continue to pace these investments to ensure attainment of full-year positive operating leverage. We also remain pleased with the credit performance of our portfolio.

Economy

Our regional economy has experienced strong growth, generally in line with or exceeding the national average. Economic and employment growth in some of our large metro areas has been well above the national average. Resulting in part from cyclically high vehicle sales and production, economic growth has been especially strong in Michigan and Indiana. Ohio’s diverse economy should benefit from a strong services sector and rising domestic demand for automobiles and other Ohio produced products. The diverse economies of Pennsylvania and Kentucky are fundamentally strong and expected to continue solid growth into next year.

7

Table of Contents

Low energy prices are generally a net benefit to the large manufacturing economies of Michigan, Ohio and Indiana, as much of the manufacturing in these areas has high petroleum inputs. However, low energy prices have been more challenging for high energy production areas. These areas are generally concentrated in localities in Eastern Ohio, Western Pennsylvania and especially in West Virginia where low coal prices have had a relatively large macroeconomic impact.

Home purchase prices are rising in our footprint states and the nation. In addition, office vacancy rates in our largest MSAs continue to improve. Further, industrial vacancy rates in most of our largest footprint MSAs have been below the national average, reflecting generally healthy industrial real estate markets.

Legislative and Regulatory

Regulatory reforms continue to be adopted, including the 2015 first quarter implementation of the Basel III regulatory capital requirements.

Basel III Regulatory Capital Requirements—In 2013, the Federal Reserve voted to adopt final capital rules implementing Basel III requirements for U.S. Banking organizations, which were effective for us beginning January 1, 2015. The final rules establish an integrated regulatory capital framework and implement in the United States the Basel III regulatory capital reforms from the Basel Committee on Banking Supervision and certain changes required by the Dodd-Frank Act. Consistent with the international Basel framework, the final rule includes a new regulatory minimum ratio of common equity tier 1 capital to risk-weighted assets. The rule also raises the minimum ratio of tier 1 capital to risk-weighted assets and includes a minimum leverage ratio of 4%. The Basel III capital rules establish two methodologies for calculating risk-weighted assets, the advanced and standardized approaches. We are subject to the standardized approach for calculating risk-weighted assets. The implementation of the Basel III capital requirements is transitional and phases-in through the end of 2018.

Conforming Covered Activities to Implement the Volcker Rule—On December 10, 2013, the Federal Reserve, the OCC, the FDIC, the CFTC and the SEC issued final rules to implement the Volcker Rule contained in section 619 of the Dodd-Frank Act, and established July 21, 2015, as the end of the conformance period. The Volcker Rule prohibits an insured depository institution and any company that controls an insured depository institution (such as a bank holding company), and any of their subsidiaries and affiliates (referred to as “banking entities”) from: (i) engaging in “proprietary trading” and (ii) investing in or sponsoring certain types of funds (“covered funds”) subject to certain limited exceptions. These prohibitions impact the ability of U.S. banking entities to provide investment management products and services that are competitive with nonbanking firms generally and with non-U.S. banking organizations in overseas markets. The rule also effectively prohibits short-term trading strategies by any U.S. banking entity if those strategies involve instruments other than those specifically permitted for trading. Because the Company has over $50 billion in assets, it is subject to Volcker enhanced compliance requirements. As such the company has completed Volcker Rule due diligence, built its compliance program, and implemented training and on-going reporting requirements. Huntington believes it has achieved required conformance on July 21, 2015 and will deliver the required attestation on or before March 31, 2016.

Expectations – 2015

We are bullish about the Midwest economy creating increasing opportunities for us with both our consumer and business customers. We saw momentum build across our businesses as loan and deposit growth accelerated in the back half of the quarter and our pipelines grew. We will continue to grow our loan portfolio prudently while remaining aligned with our aggregate moderate-to-low risk appetite. We also will deliver full-year positive operating leverage as we balance investment in the businesses for the long term, including digital technology, data analytics, and in-store branches, with the near-term revenue outlook.

The commitment to positive operating leverage for full-year 2015, excluding Significant Items and net MSR activity, is both inclusive and exclusive of the impact of HTF. We continue to expect noninterest expense growth of 2-4% for the year, excluding Significant Items and the recurring expense related to HTF. On a reported basis, we expect quarterly noninterest expense will remain near the 2015 second quarter level for the remainder of 2015.

Overall, asset quality metrics are expected to remain near current levels across the portfolio. Moderate quarterly volatility is expected given the absolute low level of problem assets and credit costs. We anticipate NCOs will remain within or below our long-term normalized range of 35 to 55 basis points.

The effective tax rate for the remainder of 2015 is expected to be in the range of 24% to 27%.

8

Table of Contents

DISCUSSION OF RESULTS OF OPERATIONS

This section provides a review of financial performance from a consolidated perspective. It also includes a “Significant Items” section that summarizes key issues important for a complete understanding of performance trends. Key Unaudited Condensed Consolidated Balance Sheet and Unaudited Condensed Statement of Income trends are discussed. All earnings per share data are reported on a diluted basis. For additional insight on financial performance, please read this section in conjunction with the “Business Segment Discussion.”

Table 1—Selected Quarterly Income Statement Data (1)

9

Table of Contents

10

Table of Contents

Table 2—Selected Year to Date Income Statement Data (1)

11

Table of Contents

Significant Items

Definition of Significant Items

From time-to-time, revenue, expenses, or taxes are impacted by items judged by us to be outside of ordinary banking activities and / or by items that, while they may be associated with ordinary banking activities, are so unusually large that their outsized impact is believed by us at that time to be infrequent or short-term in nature. We refer to such items as Significant Items. Most often, these Significant Items result from factors originating outside the Company; e.g., regulatory actions / assessments, windfall gains, changes in accounting principles, one-time tax assessments / refunds, litigation actions, etc. In other cases, they may result from our decisions associated with significant corporate actions outside of the ordinary course of business; e.g., merger / restructuring charges, recapitalization actions, goodwill impairment, etc.

Even though certain revenue and expense items are naturally subject to more volatility than others due to changes in market and economic environment conditions, as a general rule volatility alone does not define a Significant Item. For example, changes in the provision for credit losses, gains / losses from investment activities, asset valuation writedowns, etc., reflect ordinary banking activities and are, therefore, typically excluded from consideration as a Significant Item.

We believe the disclosure of Significant Items provides a better understanding of our performance and trends to ascertain which of such items, if any, to include or exclude from an analysis of our performance; i.e., within the context of determining how that performance differed from expectations, as well as how, if at all, to adjust estimates of future performance accordingly. To this end, we adopted a practice of listing Significant Items in our external disclosure documents; e.g., earnings press releases, investor presentations, Forms 10-Q and 10-K.

Significant Items for any particular period are not intended to be a complete list of items that may materially impact current or future period performance.

Significant Items Influencing Financial Performance Comparisons

Earnings comparisons were impacted by the Significant Items summarized below:

12

Table of Contents

The following table reflects the earnings impact of the above-mentioned Significant Items for periods affected by this Results of Operations discussion:

Table 3—Significant Items Influencing Earnings Performance Comparison

13

Table of Contents

Net Interest Income / Average Balance Sheet

The following tables detail the change in our average balance sheet and the net interest margin:

Table 4—Consolidated Quarterly Average Balance Sheets