Does Sam Kill Crowley?

As Crowley looks for Dean, Sam, hidden inside a nearby stairwell, shoots Crowley with a devil's trap bullet, binding Crowley's powers and effectively incapacitating him.

Who kills Crowley?

Lucifer eventually escapes and apparently kills Crowley, something the Winchesters learn about from the British Men of Letters. In "All Along the Watchtower", Crowley is revealed to have survived by possessing a rat before Lucifer "killed" him.

What episode does Crowley die?

In "All Along The Watchtower," Supernatural fans watched stunned as Crowley and Castiel were killed. The first of the two to die was Crowley, the King of Hell himself.