| Code | Name | Region |
|---|---|---|
| USOOM | Bloomer | WI |
| USAAC | Bloomfield | CT |
| USLMH | Bloomfield | IA |
| USBMF | Bloomfield | IN |
| USBF8 | Bloomfield | KY |
| USFQA | Bloomfield | MI |
| USOFB | Bloomfield | MO |
| USOFE | Bloomfield | NE |
| USIVL | Blairsville | GA |
| USBSI | Blairsville | PA |
| USBMU | Blakely | GA |
| USBYW | Blakely Island | WA |
| USFKE | Blakeslee | OH |
| USBJZ | Blakeslee | PA |
| USJBN | Blanca | CO |
| USI95 | Blanchard | IA |
| USB8D | Blanchard | ID |
| USAHQ | Blanchard | MI |
| USB8C | Blanchard | OK |
| USBCX | Blanchester | OH |
| USB5L | Blanco | TX |
| USB2T | Blanconia | TX |
| USBDQ | Bland | MO |
| USBDC | Bland | VA |
| USFB8 | Blandford | MA |
| USBDG | Blanding | UT |
| US4BV | Blandinsville | IL |
| USBDN | Blandon | PA |
| USBXO | Bladenboro | NC |
| USBDZ | Bladensburg | MD |
| USJIB | Blain | PA |
| USQBE | Blaine | GA |
| US9BI | Blaine | ME |
| USBNE | Blaine | MN |
| USVBI | Blaine | TN |
| USBWS | Blaine | WA |
| USBLA | Blaine | WI |
| USBAJ | Blair | NE |
| USBIW | Blair | SC |
| USVBA | Blair | WI |
| USBV6 | Blairesville | GA |
| USBSV | Blairs | VA |
| USBXZ | Blairs | VA |
| USBZ5 | Blairsburg | IA |
| USGKZ | Blairsden-graeagle | CA |
| USQWN | Blairstown | IA |
| USQXB | Blairstown | MO |
| USB4L | Blairstown | NJ |
| USBQM | Black Mountain | NC |
| USLCV | Black River Falls | WI |