July 29, 2016 is the deadline for windows 10 free upgrade.

Before rushing out to upgrade, take into consideration of the following:

1. Windows 7 is supported until 2020, are you planing on keeping your computer past this date?
2. Check all your software to make sure it is compatible with Windows 10. Quickbooks, Office, ERP, etc.
3. Windows 7 to Windows 10 is a significant upgrade. A clean install is always recommended.

Source: http://www.geek.com/microsoft/microsoft-warns-free-windows-10-upgrades-will-end-after-that-its-119-1654236/