Reg FD Disclosure

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): April 27, 2005 ALEXANDER'S, INC. (Exact Name of Registrant as Specified in Charter) Delaware (State or Other Jurisdiction of Incorporation) No. 001-06064 (Commission File Number) No. 51-0100517 (IRS Employer Identification No.) 210 Route 4 East Paramus, NJ (Address of Principal Executive offices) 07652 (Zip Code) Registrant's telephone number, including area code: (201) 587-8541 Former name or former address, if changed since last report: N/A 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 Instructions A.2.): o Written communications pursuant to Rule 425 under the Securities Act (17 CFR 230.425) ý Soliciting material pursuant to Rule 14a-12 under the Exchange Act (17 CFR 240.14a-12) o Pre-commencement communications pursuant to Rule 14d-2(b) under the Exchange Act (17 CFR 240.14d-2(b)) o Pre-commencement communications pursuant to Rule 13e-4(c) under the Exchange Act (17 CFR 240.13e-4(c)) Item 7.01 Regulation FD Disclosure. On April 27, 2005, Vornado Realty Trust mailed to its shareholders its Annual Report for the year ended December 31, 2004. The Chairman's Letter contained within the Annual Report contains information that may be of interest to investors in Alexander's, Inc.. A copy of the Chairman's Letter is attached hereto as Exhibit 99.1. Item 9.01 Financial Statements, Pro Forma Financial Information and Exhibits. (c) Exhibits. 99.1 Chairman's Letter from Vornado Realty Trust's Annual Report for the year ended December 31, 2004. 2 SIGNATURE 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. ALEXANDER'S, INC. (Registrant) By: /s/ JOSEPH MACNOW Name: Joseph Macnow Title: Executive Vice President And Chief Financial Officer Date: April 27, 2005 3 QuickLinks SIGNATURE