Green’s Dictionary of Slang

having left, esp. when leaving suddenly; thus I’m out of here, a phr. of farewell.

[c.1929		W.R. Burnett Little Caesar (1932) 19: I’ll be out of here in less than that].
1971		Current Sl. VI 11: We’re out of here! v. To leave (imperative in the sense of ‘Let’s get out of here.’).
1978		W. Diehl Sharky’s Machine 129: Now I want outa here!
1989		M. Amis London Fields 34: Listen, we’re out of here. We are gone.
1993		Tarantino & Avery Pulp Fiction [film script] 99: That’s all Bitch needs to see. He’s outta there.
2006		F.X. Toole Pound for Pound 154: Please tell those in charge that I’m outa here.