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): October 4, 2011

AVAYA INC.

(Exact Name of Registrant as Specified in its Charter)

Registrant’s telephone number, including area code: (908) 953-6000

N/A

(Former Name or Former Address, if Changed Since Last Report)

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:

Item 8.01. Other Events.

On October 4, 2011, Avaya Inc. (the “Company”) issued a press release announcing that it had acquired Sipera Systems, Inc., a Delaware corporation (“Sipera”). A copy of the press release is attached hereto as Exhibit 99.1 and is incorporated herein by reference.

This current report on Form 8-K contains “forward-looking statements.” All statements other than statements of historical fact are “forward-looking” statements for purposes of the U.S. federal and state securities laws. These statements may be identified by the use of forward looking terminology such as “anticipate,” “believe,” “continue,” “could,” “estimate,” “expect,” “intend,” “may,” “might,” “plan,” “potential,” “predict,” “should” or “will” or the negative thereof or other variations thereon or comparable terminology. We have based these forward-looking statements on our current expectations, assumptions, estimates and projections. While we believe these expectations, assumptions, estimates and projections are reasonable, such forward-looking statements are only predictions and involve known and unknown risks and uncertainties, many of which are beyond our control. These factors, including those discussed in the Company’s Annual Report on Form 10-K for the fiscal year ended September 30, 2010 and those disclosed in the Company’s Quarterly Report on Form 10-Q for the quarter ended June 30, 2011, may cause our actual results, performance or achievements to differ materially from any future results, performance or achievements expressed or implied by these forward-looking statements. For a further list and description of such risks and uncertainties, please refer to the Company’s filings with the SEC that are available at www.sec.gov. We caution you that the list of important factors included in the Company’s SEC filings may not contain all of the material factors that are important to you. In addition, in light of these risks and uncertainties, the matters referred to in the forward-looking statements contained in this report may not in fact occur. We undertake no obligation to publicly update or revise any forward-looking statement as a result of new information, future events or otherwise, except as otherwise required by law.

SIGNATURES

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.