| Code | Name | Region |
|---|---|---|
| USBOI | Boise | ID |
| USBO7 | Boise City | OK |
| USBK5 | Bokeelia | FL |
| USB2G | Boligee | AL |
| USB27 | Bolinas | CA |
| USBG4 | Boling | TX |
| USBNK | Bolingbrook | IL |
| USZXT | Bolington | VA |
| USXDB | Bluff | UT |
| USBIF | Bluff City | TN |
| USBC2 | Bluff Creek | LA |
| USB6D | Bluff Dale | TX |
| USLFF | Bluffdale | UT |
| USBJU | Bluffs | IL |
| USBL9 | Bluffton | GA |
| USBFE | Bluffton | IN |
| USBHK | Bluffton | OH |
| USBFQ | Bluffton | SC |
| US3BL | Blum | TX |
| USBLH | Blythe | CA |
| USB5D | Blythedale | MO |
| USBYH | Blytheville | AR |
| USUBV | Blythewood | SC |
| USBDM | Boardman | OH |
| USBDA | Boardman | OR |
| USOAZ | Boaz | AL |
| USBCG | Boca Grande | FL |
| USBCT | Boca Raton | FL |
| USB8A | Blue Grass | IA |
| US8BU | Blue Hill | ME |
| USBCU | Blue Island | IL |
| USBUL | Blue Lake | CA |
| US5BM | Blue Mound | IL |
| US6BM | Blue Mound | KS |
| USKBM | Blue Mound | TX |
| US2BM | Blue Mounds | WI |
| USXCN | Blue Mountain | MS |
| USBP6 | Blue Point | NY |
| USBPD | Blue Rapids | KS |
| USYBR | Blue Ridge | GA |
| USUDG | Blue Ridge | VA |
| USBJP | Blue Ridge Summit | PA |
| USB9R | Blue River | WI |
| USBZY | Blue Springs | MO |
| USBPR | Blue Springs | MS |
| USJBP | Blue Springs | NE |
| USVBS | Bluefield | VA |
| USAFL | Bluefield | WV |
| USBSB | Bloomsburg | PA |
| USBBQ | Bloomsbury | NJ |