Microsoft's free Windows 10 upgrade deal is looking better and better all the time. For if you already own a genuine Windows PC, you could be saving yourself upwards of a hundred to almost two hundred dollars.

Microsoft confirmed Monday that the company will sell Windows 10 at retail for the same price as Windows 8.1: $119 for Windows 10 Home, $199 for Windows 10 Professional, and $99 for a Windows 10 Pro Pack to jump from a licensed copy of Windows 10 Home to the Professional version.

That means, unfortunately, that the price leaked by Newegg's retail site over the weekend for Windows 10 Home was incorrect. NewEgg pegged the price of the Windows 10 Home Edition at $109, and the Professional version at $149. It also claimed that the software would be released on August 31.

On July 29, according to Microsoft, you'll be able either to download Windows 10 or buy a new Windows 10 PC from retailers. And if you click the "reservation link" that Microsoft is pushing via its most recent updates to Windows 7 and Windows 8.1, you can apparently sign up to preload the software just as soon as it's ready. Microsoft promises that upgrades will be free for the "supported lifespan" of the device, although it hasn't explained what that phrase actually means.

As of press time, NewEgg changed the release date of the software to reflect the July 29 launch date that Microsoft officially announced early Monday morning; the company has not yet announced a revision to its published prices. However, if you act fast you may be able to score a discount. "If your pre-order is placed successfully, we will honour the price we advertised," an online sales agent said in a chat.

Nevertheless, the free upgrade that Microsoft has made available to Windows 8.1 and Windows 7 users is looking like a fantastic savings. Remember, it's only for a year's time, though, so make sure you take advantage of it before it disappears.