- Unalga Island
- Unalga Island
- Unavikshak Island
- Unga
- Unga Island
- Ungalik
- Ungalikthluk
- Ungluchin
- Unglulagan
- Ungluugamax
- Unglux
- Unguchiing Achidan Tanangis
- Unguchiing Hachan Tangingis
- Unimak Island
- Unishka Island
- Unlucky Island
- Upper Slate Creek
- Urilof Island
- Ushagat Island
- Usibelli
- Uski Island
- Utesistoi Island
- Utopia
- Utopia Creek
- Utukakarvik
- Uuyax
- Uyak
- Uyak Island
- Uzamkum-tanasuu