| Unassuming cuebid |
| Unbalanced distribution |
| Unbalanced Swiss raise |
| Unbeatable |
| Unbid minor forcing |
| Unbid suit |
| Unblocking |
| Unconstructive |
| Under the gun |
| Underbid |
| Underbidder |
| Underlead |
| Underruff |
| Undertrump |
| Undouble |
| Unlimited bid |
| Unmakable |
| Unpenalty double |
| Unusual jumps |
| Unusual Notrump |
| Unusual over unusual |
| Unusual positive |
| Up the line |
| Up to |
| Up to strength |
| Up to weakness |
| Upper suits cuebid |
| Uppercut |
| Upside-down signals |
| Useful space principle |
| Utility |
