What is an Offset I Formation in Football? An offset I formation in football is a variation of an I formation where the fullback sets up behind the guard instead of behind the quarterback. A typical offset I features two wide receivers and a tight end as pictured above, but other variations exist with two tight ends or flankers.

This formation is commonly called an Offset I. In either case, the fullback lines up roughly a yard laterally to his usual position. Strong refers to a move towards the TE side of the formation (Primary TE, or flanker's side when in a "big" 2TE set), weak in the opposite direction. These modifications have little effect on expected play call.

Sometimes, the fullback will line up at the same depth but with slight adjustment, 1-2 yards to either side, lining up behind a guard instead of center. This is called the offset I, and would be called either strong I or weak I depending on which side of center the fullback lines up on.

The I-Formation was named that because of how the backs are lined up directly behind the quarterback. This will be the case on just about every play that’s run out of the I-Formation, although the fullback may split out a little wider in what’s known as an off-set I-Formation.