The date was included in a U.S. Securities and Exchange Commission filing by Microsoft, ZDNet reported Tuesday.
"The next version of our operating system, Windows 8, will be generally available on October 26, 2012," Microsoft said in its filing. "At that time, we will begin selling the Surface, a series of Microsoft-designed and manufactured hardware devices."
No release date for the Surface had been given at the time the tablet was announced in June, although it was widely expected to coincide with Windows 8 availability.
Microsoft has not yet announced if the Oct. 26 release date covers the United States only or if it will include international markets.