Users with an iPhone 3GS, iPhone 4, iPhone 4S, fourth-generation iPod Touch, iPad 2 or third-generation iPad will be able to download the software update for free on September 19.
iOS 6 will also come pre-loaded on the newly announced iPhone 5, which launches on September 21.
Apple officially unveiled its latest mobile operating system at its Worldwide Developers Conference in June.
The new software will feature more than 200 enhancements, including an upgrade to Siri, deep Facebook integration, and a Maps service to rival Google.
Apple Maps will feature turn-by-turn navigation, Siri support and a 3D flyover feature, enabling users to scroll around landmarks and cities.
iOS 6 also takes advantage of Apple's iCloud Tabs, allowing users to resume viewing bookmarked web pages on other Apple devices.
Apple demonstrated the new Passbook feature during the iPhone 5 unveiling event in San Francisco, showing off a shredder option for deleting old tickets.
The iPhone 5 is made entirely of glass and aluminium, is being touted as the "thinnest smartphone in the world" at 7.6mm in depth.
Weighing in at 112 grams, the iPhone 5 is 20% lighter than the current generation iPhone 4S.
As previously rumoured, the device sports a larger 4-inch Retina display capable of displaying 326 pixels per inch with a resolution of 1136 x 640. Apple apps such as iWork suite and iPhoto have been optimised for a bigger screen, as has some third-party software.
The screen offers 44% more colour saturation than iPhone 4S and uses in-cell technology, integrating the touch layer in the LCD allowing for a thinner form factor.
Apple's iPhone 5 is backed by ultrafast wireless technology, including GPRS, EDGE, EV-DO, HSPA+ and LTE. It will be available in the UK on Everything Everywhere's EE network.
> Apple iPhone 5 launch: Live Blog
> iPhone 5 announced by Apple
Photo gallery - Apple's iPhone 5 launch event in pictures:
Copyright: PA Images Jeff Chiu/AP