A preview version of the shop is now available to sample ahead of Microsoft's next-generation operating system in October.
The Windows 8 edition of 7digital hosts more than 20 million tracks, and will run across all versions of the OS, including the ARM-based Windows 8 RT and the Windows Phone 8 mobile edition.
The preview app runs on both desktop and metro versions and features 7 digital's music discovery service and 30-second previews of all tracks.
7digital CEO Ben Drury said: "The potential of Windows 8 is huge. Microsoft's renewed commitment to the tablet space, and development of the Surface hardware, means there could be millions of devices in the market by the end of next year.
"We believe this offers us a significant market opportunity as a digital music provider."
Microsoft's Windows 8 operating system is released for desktops, laptops and tablets on October 26.