I owe you one
Also found in: Acronyms.
owe (one) one
To be indebted to one for something they did. Thanks for not ratting me out to the boss about being late this morning—I owe you one! OK, you can borrow my car, but you owe me one!
I owe you one.
Inf. Thank you, now I owe you a favor.; I owe you something similar in return. Bob: I put the extra copy of the book on your desk. Sue: Thanks, I owe you one. Bill: Let me pay for your drink. Bob: Thanks a lot, I owe you one.