| Bastrop | 95,000 | Bastrop | Texas | Austin-Waco, TX | View → |
| Bay | 103,000 | Bay City | Michigan | Detroit, MI-Toledo, OH | View → |
| Bayfield | 15,000 | Washburn | Wisconsin | Green Bay, WI-Duluth, MN | View → |
| Beaver | 5,300 | Beaver | Oklahoma | Amarillo, TX | View → |
| Becker | 36,000 | Detroit Lakes | Minnesota | Fargo, ND | View → |
| Belknap | 63,000 | Laconia | New Hampshire | Boston-Springfield, MA | View → |
| Bell | 380,000 | Killeen | Texas | Austin-Waco, TX | View → |
| Bennington | 36,000 | Bennington | Vermont | Albany-Utica-Elmira, NY | View → |
| Benson | 6,500 | Minnewaukan | North Dakota | Fargo, ND | View → |
| Bent | 5,800 | Las Animas | Colorado | Denver-Colorado Springs, CO | View → |
| Benton | 25,000 | Vinton | Iowa | Cedar Rapids, IA | View → |
| Berkeley | 250,000 | Moncks Corner | South Carolina | Charleston-Florence, SC | View → |
| Berkshire | 125,000 | Pittsfield | Massachusetts | Albany-Utica-Elmira, NY | View → |
| Bernalillo | 690,000 | Albuquerque | New Mexico | Albuquerque, NM | View → |
| Berrien | 155,000 | Niles | Michigan | Chicago, IL | View → |
| Bibb | 22,300 | Centreville | Alabama | Birmingham-Huntsville, AL | View → |
| Billings | 1,000 | Medora | North Dakota | Bismarck, ND | View → |
| Bingham | 48,000 | Blackfoot | Idaho | Boise-Pocatello, ID | View → |
| Black Hawk | 133,000 | Waterloo | Iowa | Cedar Rapids, IA | View → |
| Blaine | 24,000 | Hailey | Idaho | Boise-Pocatello, ID | View → |
| Blanco | 12,200 | Johnson City | Texas | Austin-Waco, TX | View → |
| Bland | 6,500 | Bland | Virginia | Charleston-Bluefield, WV | View → |
| Blount | 59,100 | Oneonta | Alabama | Birmingham-Huntsville, AL | View → |
| Boise | 7,500 | Idaho City | Idaho | Boise-Pocatello, ID | View → |
| Bonneville | 125,000 | Idaho Falls | Idaho | Boise-Pocatello, ID | View → |
| Boone | 21,000 | Madison | West Virginia | Charleston-Bluefield, WV | View → |
| Boone | 54,000 | Belvidere | Illinois | Chicago, IL | View → |
| Boone | 140,000 | Florence | Kentucky | Cincinnati-Dayton, OH | View → |
| Boone | 27,000 | Boone | Iowa | Des Moines, IA | View → |
| Bosque | 18,400 | Clifton | Texas | Dallas-Fort Worth, TX | View → |
| Bottineau | 6,400 | Bottineau | North Dakota | Bismarck, ND | View → |
| Boulder | 330,000 | Boulder | Colorado | Denver-Colorado Springs, CO | View → |
| Bowman | 3,100 | Bowman | North Dakota | Bismarck, ND | View → |
| Box Butte | 10,500 | Alliance | Nebraska | Denver-Colorado Springs, CO | View → |
| Boyd | 47,000 | Ashland | Kentucky | Charleston-Bluefield, WV | View → |
| Bracken | 8,500 | Brooksville | Kentucky | Cincinnati-Dayton, OH | View → |
| Branch | 44,000 | Coldwater | Michigan | Grand Rapids, MI | View → |
| Braxton | 12,500 | Sutton | West Virginia | Charleston-Bluefield, WV | View → |
| Brazos | 240,000 | Bryan | Texas | Austin-Waco, TX | View → |
| Bremer | 24,500 | Waverly | Iowa | Cedar Rapids, IA | View → |
| Brewster | 9,500 | Alpine | Texas | El Paso-Odessa, TX | View → |
| Briscoe | 1,400 | Silverton | Texas | Amarillo, TX | View → |
| Broomfield | 85,000 | Broomfield | Colorado | Denver-Colorado Springs, CO | View → |
| Brown | 6,500 | Mount Sterling | Illinois | Champaign-Peoria, IL | View → |
| Brown | 44,400 | Georgetown | Ohio | Cincinnati-Dayton, OH | View → |
| Brown | 270,000 | Green Bay | Wisconsin | Green Bay, WI-Duluth, MN | View → |
| Buchanan | 21,000 | Independence | Iowa | Cedar Rapids, IA | View → |
| Buncombe | 270,000 | Asheville | North Carolina | Greenville, SC-Asheville, NC | View → |
| Bureau | 34,000 | Princeton | Illinois | Davenport, IA-Moline, IL | View → |
| Burke | 2,100 | Bowbells | North Dakota | Bismarck, ND | View → |
