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) February 25, 2011

AirTran Holdings, Inc.

(Exact name of registrant as specified in its charter)

State of Incorporation: Nevada

9955 AirTran Boulevard, Orlando, Florida 32827

(Address of principal executive offices) (Zip Code)

(407) 318-5600

(Registrant’s telephone number, including area code)

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

On February 25, 2011, Robert L. Fornaro, Chairman, President and Chief Executive Officer of AirTran Holdings, Inc. (“AirTran”) testified before the United States Senate Committee on the Judiciary Subcommittee on Antitrust, Competition Policy and Consumer Rights in connection with the proposed merger between AirTran and Southwest Airlines Co. (“Southwest”). Mr. Fornaro also provided a written statement to the Subcommittee. In both his written statement and during his testimony, Mr. Fornaro discussed certain forward-looking information, including certain information regarding the potential for growth of Southwest Airlines and AirTran as a combined company. A copy of Mr. Fornaro’s written statement is included within Exhibit 99.1 and incorporated herein by reference.

The information in this Form 8-K is being furnished under Item 7.01 and shall not be deemed “filed” for the purposes of Section 18 of the Securities and Exchange Act of 1934 (the “Exchange Act”), or otherwise subject to the liabilities of such section, nor shall such information be deemed incorporated by reference in any filing under the Securities Act of 1933 or the Exchange Act, except as shall be expressly set forth by specific reference in such a filing.

Important Information for Investors and Stockholders

This communication does not constitute an offer to sell or the solicitation of an offer to buy any securities or a solicitation of any vote or approval. The proposed acquisition of AirTran Holdings, Inc. (“AirTran”) by Southwest Airlines Co. (“Southwest”) will be submitted to the stockholders of AirTran for their consideration. In connection therewith, Southwest has filed a registration statement on Form S-4 with the Securities and Exchange Commission (the “SEC”) that includes a proxy statement of AirTran that also constitutes a prospectus of Southwest. Southwest and AirTran also plan to file other documents with the SEC regarding the proposed transaction. AIRTRAN URGES INVESTORS AND SECURITY HOLDERS TO READ THE PROXY STATEMENT/PROSPECTUS AND ANY OTHER RELEVANT DOCUMENTS FILED WITH THE SEC CAREFULLY AND IN THEIR ENTIRETY BECAUSE THEY CONTAIN IMPORTANT INFORMATION ABOUT THE PROPOSED TRANSACTION. Investors and security holders may obtain free copies of the proxy statement/prospectus and other documents containing important information about Southwest and AirTran through the website maintained by the SEC at http://www.sec.gov/. Copies of the documents filed with the SEC by Southwest are available free of charge on Southwest’s website at http://www.southwest.com/ under the tab “Investor Relations” or by contacting Southwest’s Investor Relations Department at (214) 792-4415. Copies of the documents filed with the SEC by AirTran are available free of charge on AirTran’s website at http://www.airtran.com/ under the tab “Investor Relations” or by contacting AirTran’s Investor Relations Department at (407) 318-5188.

Southwest, AirTran and certain of their respective directors and executive officers may be deemed to be participants in the solicitation of proxies from the stockholders of AirTran in connection with the proposed transaction. Information about the directors and executive officers of Southwest is set forth in its proxy statement for its 2010 annual meeting of shareholders, which was filed with the SEC on April 16, 2010. Information about the directors and executive officers of AirTran is set forth in its proxy statement for its 2010 annual meeting of stockholders, which was filed with the SEC on April 2, 2010. These documents can be obtained free of charge from the sources indicated above. Other information regarding the participants in the proxy solicitation and a description of their direct and indirect interests, by security holdings or otherwise, is contained in the proxy statement/prospectus and other relevant materials filed with the SEC.

Cautionary Statement Regarding Forward-Looking Statements

This communication contains “forward-looking statements” within the meaning of the safe harbor provisions of the Private Securities Litigation Reform Act of 1995 that are not limited to historical facts, but reflect AirTran’s and Southwest’s current beliefs, expectations or intentions regarding future events. Words such as “may,” “will,” “could,” “should,” “expect,” “plan,” “project,” “intend,” “anticipate,” “believe,” “estimate,” “predict,” “potential,” “pursue,” “target,” “continue,” and similar expressions are intended to identify such forward-looking statements. These forward-looking statements include, without limitation, AirTran’s and Southwest’s expectations with respect to the synergies, costs and other anticipated financial impacts of the proposed transaction; future financial and operating results of the combined company; the combined company’s plans, objectives, expectations and intentions with respect to future operations and services; approval of the proposed transaction by Shareholders and by governmental regulatory authorities; the satisfaction of the closing conditions to the proposed transaction; and the timing of the completion of the proposed transaction.

All forward-looking statements involve significant risks and uncertainties that could cause actual results to differ materially from those in the forward-looking statements, many of which are generally outside the control of AirTran and Southwest and are difficult to predict. Examples of such risks and uncertainties include, but are not limited to, (1) the possibility that the proposed transaction is delayed or does not close, including due to the failure to receive AirTran’s required stockholder approval or required regulatory approvals, the taking of governmental action (including the passage of legislation) to block the transaction, or the

failure of other closing conditions, and (2) the possibility that the expected synergies will not be realized, or will not be realized within the expected time period, because of, among other things, significant volatility in the cost of aircraft fuel, the significant capital commitments of AirTran and Southwest, the impact of labor relations, global economic conditions, fluctuations in exchange rates, competitive actions taken by other airlines, terrorist attacks, natural disasters, difficulties in integrating the two airlines, the willingness of customers to travel by air, actions taken or conditions imposed by the U.S. and foreign governments or other regulatory matters, excessive taxation, further industry consolidation and changes in airlines alliances, the availability and cost of insurance and public health threats.

AirTran cautions that the foregoing list of factors is not exclusive. Additional information concerning these and other risk factors is contained in AirTran’s and Southwest’s most recently filed Annual Reports on Form 10-K, subsequent Quarterly Reports on Form 10-Q, recent Current Reports on Form 8-K, and other SEC filings. All subsequent written and oral forward-looking statements concerning AirTran, Southwest, the proposed transaction or other matters and attributable to AirTran or any person acting on their behalf are expressly qualified in their entirety by the cautionary statements above.

AirTran undertakes no obligation to publicly update any of these forward-looking statements to reflect events or circumstances that may arise after the date hereof.

Signature(s)

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.

Exhibit Index