Halo Reach, Halo Wars, Halo 3 & 4 DLC FREE via the Xbox Store

Xbox Store

Halo DLC

In preparation of Halo 3, Halo 3: ODST, Halo 4, and Halo: CE Anniversary joining Xbox One backward compatibility later this year, several Halo DLC are now permanently free. Check below for the full list.

Halo 3

Halo 4

Halo Reach

Halo Wars

You can check out more info about the Halo Summer Celebration here.