This one is a bit timelier than most of my previous Windows 8 tips, and it’s likewise very straightforward. If you’re planning to upgrade an existing PC to Windows 8, you need to do so soon in order to save a ton of money. And that’s true whether you wish to buy a retail upgrade or do so electronically.

I’ve already written a lot about upgrading to Windows 8. But with Microsoft reminding users that it will soon jack up the price on the Windows 8 Upgrade and eliminate the temporary promotional pricing as previously promised, your time is running out.

There are a number of upgrade strategies to consider.

If you purchase(d) a new PC running Windows 7 between June 2, 2012 and January 31, 2013, you qualify for the Windows Upgrade Offer. This supplies you with the Upgrade version of Windows 8 Pro for just $14.99, the cheapest mainstream way to upgrade to Microsoft’s latest operating system.

If you are using any modern PC that originally came with Windows XP, Windows Vista, or Windows 7, you qualify for the Windows 8 Pro Upgrade. (This is the reason Microsoft isn’t selling a “Full” version of Windows 8 as it did with previous Windows versions; all PCs that can run Windows 8 qualify for the upgrade.)

In this case, you have two options. You can purchase the Windows 8 Pro Upgrade retail package for just $69.99. (Buy it now at the Microsoft Store.) This offer lasts until January 31, 2013, however. After that date, the same retail package will cost $199.99. (Or you can get Windows 8 “Core” Upgrade for $129.99; this is not currently available for sale anywhere.)

Or you can save even more money and purchase the electronic download of Windows 8 Pro for just $39.99. As with the retail version, the price of this upgrade version will jump to $199.99 on February 1, 2013, so you need to act fast.

I have been recommending the electronic download version of the Windows 8 Pro Upgrade for several months, and for good reason: It features a web-based installer that includes additional tools—the Upgrade Advisor and Windows Easy Transfer—that make the upgrade process go much, much more smoothly than the traditional retail package. Read Windows 8 Feature Focus: Web-Based Setup and Windows 8 Tip: Use the Web-Based Installer for more information.

Of course, some people have different needs. You can in fact perform a clean (or “full”) install of Windows 8 using the Upgrade media. Refer to Clean Install Windows 8 with Upgrade Media for the details and remember that every one of the tips in Clean Install Windows 7 with Upgrade Media works if you have trouble activating. And don’t fear the FUD-meisters: Clean installing Windows 8 with Upgrade media is perfectly legal.

If you’re running a 32-bit version of Windows XP, Vista, or 7, and wish to upgrade to a 64-bit version of Windows 8, please refer to Windows 8 Upgrade: 32-bit to 64-bit for the lowdown. It’s not completely straightforward or seamless, but you do have options.

And if you are coming from a previous version of Windows, be sure to check out my handy guides to what is supported: Windows 8 Tip: Upgrade from Windows XP, Windows 8 Tip: Upgrade from Windows Vista, and Windows 8 Tip: Upgrade from Windows 7.

And don’t get stuck after upgrading. Windows 8 Tip: Create Setup Media After Using the Web Installer will help with one strange issue that occurs when you use the web-based installer but don’t think to create Setup media during the process. (Which I recommend you do, just in case.)

Folks, you have a few weeks left before Windows 8 Pro Upgrade prices shoot through the roof. But you don’t have to be a statistic. Backup your PC and then save a ton of money by upgrading today.