owe someone one
Favor debt outstanding
To owe someone one is to be indebted to them for a favor: Thanks for covering my shift—I owe you one.
The "one" is deliberately vague, implying a future favor of roughly equal value.
The phrase acknowledges informal social debt without specifying repayment terms.
- obligeRequire or assist
- indebtedOwing thanks or money
- on the hookBearing responsibility for something
- reciprocateReturn in kind
- tit for tatEquivalent retaliation
quid pro quo · return the favor · good turn · pay it forward · repay · pay back · settle up · thankfulness · acknowledgment · IOU · appreciation · gratefulness · duty · moral obligation · honor bound · give-and-take · responsibility · mutuality