Starting Feb 1, 2013 the $39.99 Windows 8 Pro upgrade price increases from $39.99 to $199.99. Although Jan 31st, 2013 marks the end of Microsoft’s promotional period, the increase is more substantial that expected. So if you are considering upgrading time is of the essence. Find the Windows 8 Pro upgrade offer here.
Windows 7 computers purchased between June 2, 2012 and Jan 31, 2013 qualify for the same upgrade more deeply discounted at $14.99, and that deadline is Feb 28, 2013.
Regardless of which upgrade you purchase, you must download and install the Windows 8 Upgrade Assistant and run it on your existing Windows install before you will be able to make the purchase. But don’t delay in upgrading or your cost goes up substantially.