"I Can Only Imagine" (sometimes shortened to "Imagine") is a single recorded by Christian rock band MercyMe. Written and composed by Bart Millard, the song, based around a main piano track, was inspired by the death of Millard's father and considers what it would be like in Heaven and to be standing before God. The song was first issued as a track on MercyMe's 1999 album The Worship Project, which was released on an independent record label. The song was re-recorded and included on their 2001 major-label debut album Almost There as the fifth song on the album.

Answer this question based on the passage: who wrote the song i can only imagine? Let's have some stream of consciousness first.
This is the relevant information: Written and composed by Bart Millard, the song, based around a main piano track, was inspired by the death of Millard's father and considers what it would be like in Heaven and to be standing before God. So, the answer is Bart Millard.