| Abbreviation | Definition |
|---|---|
| UGC | Uppsala General Catalogue |
| UGHS | University General Health System |
| UGR | Used Goods Return |
| UGT | Union General de Trabajadores |
| UGTT | Union Generale des Travailleurs Tunisiens |
| UHE | Used Heavy Equipment |
| UHO | Ultimate Home Office |
| UHO | User Home Organization |
| UHQ | Ultra-High Quality |
| UI | Union Initiative |
| UID(s) | unique device identifier(s) |
| UIEE | Universal Information Exchange Environment |
| UIN | Universal Identification Number |
| UIR | University- Industry Relations |
| UIT | Unit Investment Trust |
| UKBAA | UK Business Angels Association |
| UKTI | United Kingdom Trade and Investment |
| ULB | United Legal Benefits |
| ULC | Unit Labor Cost |
| ULQ | Ultra- Low Quality |