Halo 3 PC release is set for next week and will be added to Halo The Master Chief Collection on both Steam and the Windows Store from July 14.
Those on Xbox Game Pass for PC (or Xbox Game Pass Ultimate) will be able to download and play the game as part of their regular subscription fee. The Master Chief Collection also offers Halo Reach, Halo and Halo 2 on PC. Halo 3 ODST and Halo 4 will be added to PC later this year.
All the Halo games detailed above are currently available on Xbox One inside The Master Chief Collection.
Halo The Master Chief Collection is available on both Xbox One and Windows PC. The next in the series, Halo Infinite will be showcased later this month on Xbox Series X and will also be available on Xbox One and Windows PC.