What’s Up With the Ending?

In the last chapter of Fight Club, our narrator wakes up in heaven after shooting himself in the face to kill the Tyler side of his personality.

Okay, he's not quite in heaven. He's in a hospital, as you can tell by the "rubber-soled shoes" (30.10) and "lunch tray [with] meds" (30.32). When he shot himself, he still experienced the death he'd been looking for the whole time, but with none of the permanent side effects. Like burial.

Our narrator proves himself to be pretty delusional right up to the very end of the book. He believes he's killed Tyler and gone to heaven. However, "heaven" is still populated with Project Mayhem thugs who say to our narrator, "We miss, Mr. Durden" (30.33). Even if Tyler is dead, his ideologies live on.