be quits (with someone)

1. Of two or more people, to no longer owe any money to each other. I paid you back last week, so now we're finally quits. A: "All right, I'll write you a check and then we'll be quits." B: "Sounds good." Dude, we're not quits yet—you still owe me $20!

2. To be even (with someone), typically due to having retaliated for a previous misdeed, or having returned a favor. All right, he hit you, you hit him back—please tell me you two are quits now. I helped Sarah set up the community center for her casino night in return for her helping me move, so she and I are quits now. Aren't you guys quits with each other already? How long is this stupid feud going to last?

be ˈquits (with somebody)

(informal)
1 be in a position in which neither of two people owe each other money any more: If I give you $10, then we’re quits, aren’t we?
2 have done something unpleasant to somebody who did something unpleasant to you: He crashed my motorbike last year and now I’ve crashed his car, so we’re quits.