Smile FM is a network of non-commercial, contemporary Christian radio stations in the state of Michigan owned by Superior Communications, a nonprofit organization.

Most programming originates from studios in Williamston (just east of Lansing) and is relayed (with local inserts) by an expanding number of stations throughout the state.

In June 2004, the two networks were combined to form Smile FM in a "wedding ceremony" conducted at Oldsmobile Park in Lansing.

Unlike many Christian stations, they play music with only a few short breaks for weather, news, announcements, and features.

The Smile FM Praise experiment was ended in 2009 and plans made to move that station to the northern suburbs of Detroit.

All call letters beginning with WDT (WDTE, WDTP, and WDTR) serve portions of the Detroit metropolitan area.