When Windows 10 first launched, Microsoft ran a promotion offering free upgrades for a year. While that program ended in July of 2016, free upgrades have remained available through an exception for users who take advantage of "assistive technologies." Though that exception was due to end on December 31, 2017, Microsoft has quietly extended the upgrade another couple of weeks (via MSPU).
In an update to the upgrade offer page FAQ, Microsoft now states that the upgrade offer will end on January 16.
Although intended for assistive technology users, the upgrade offer doesn't require any verification of whether you actually use assistive technologies of any sort. Essentially, the offer has acted as a loophole for anyone to secure a free upgrade following the official end of the general free upgrade program in 2016.
Once the offer expires, you'll have to shell out $119 or more to get a copy of Windows 10. If you still have Windows 7 or 8 PCs that are in need of an upgrade, however, you can head to the upgrade site to move up to Windows 10 for free before January 16.
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