| Juniata | 24,300 | Mifflintown | Pennsylvania | Harrisburg, PA | View → |
| Kalamazoo | 265,000 | Kalamazoo | Michigan | Grand Rapids, MI | View → |
| Kalkaska | 18,000 | Kalkaska | Michigan | Traverse City, MI | View → |
| Kanabec | 16,000 | Mora | Minnesota | Minneapolis-St. Paul, MN | View → |
| Kanawha | 178,000 | Charleston | West Virginia | Charleston-Bluefield, WV | View → |
| Kandiyohi | 43,500 | Willmar | Minnesota | Minneapolis-St. Paul, MN | View → |
| Kane | 530,000 | Aurora | Illinois | Chicago, IL | View → |
| Kane | 7,700 | Kanab | Utah | Salt Lake City, UT | View → |
| Kankakee | 105,000 | Kankakee | Illinois | Chicago, IL | View → |
| Karnes | 15,700 | Karnes City | Texas | San Antonio-Corpus Christi, TX | View → |
| Kauai | 73,000 | Lihue | Hawaii | Honolulu, HI | View → |
| Kaufman | 156,000 | Terrell | Texas | Dallas-Fort Worth, TX | View → |
| Kay | 44,000 | Ponca City | Oklahoma | Oklahoma City, OK | View → |
| Kearney | 6,700 | Minden | Nebraska | Lincoln, NE | View → |
| Kearny | 4,000 | Lakin | Kansas | Wichita, KS | View → |
| Keith | 8,000 | Ogallala | Nebraska | Denver-Colorado Springs, CO | View → |
| Kemper | 9,400 | De Kalb | Mississippi | Tupelo-Meridian-Greenwood, MS | View → |
| Kendall | 135,000 | Oswego | Illinois | Chicago, IL | View → |
| Kendall | 54,000 | Boerne | Texas | San Antonio-Corpus Christi, TX | View → |
| Kenedy | 400 | Sarita | Texas | San Antonio-Corpus Christi, TX | View → |
| Kennebec | 122,000 | Augusta | Maine | Portland-Bangor, ME | View → |
| Kenosha | 170,000 | Kenosha | Wisconsin | Milwaukee, WI | View → |
| Kent | 20,000 | Chestertown | Maryland | Baltimore, MD | View → |
| Kent | 680,000 | Grand Rapids | Michigan | Grand Rapids, MI | View → |
| Kent | 170,000 | Warwick | Rhode Island | Hartford, CT-Providence, RI | View → |
| Kent | 750 | Jayton | Texas | Lubbock-Abilene, TX | View → |
| Kent | 186,300 | Dover | Delaware | Philadelphia, PA | View → |
| Kenton | 167,000 | Covington | Kentucky | Cincinnati-Dayton, OH | View → |
| Keokuk | 10,200 | Sigourney | Iowa | Cedar Rapids, IA | View → |
| Kern | 920,000 | Bakersfield | California | Los Angeles-San Diego, CA | View → |
| Kerr | 54,000 | Kerrville | Texas | San Antonio-Corpus Christi, TX | View → |
| Kershaw | 67,000 | Camden | South Carolina | Columbia, SC | View → |
| Kewaunee | 20,500 | Kewaunee | Wisconsin | Green Bay, WI-Duluth, MN | View → |
| Keweenaw | 2,100 | Eagle River | Michigan | Marquette, MI | View → |
| Keya Paha | 800 | Springview | Nebraska | Lincoln, NE | View → |
| Kidder | 2,400 | Steele | North Dakota | Bismarck, ND | View → |
| Kimball | 3,600 | Kimball | Nebraska | Denver-Colorado Springs, CO | View → |
| Kimble | 4,100 | Junction | Texas | Austin-Waco, TX | View → |
| King | 2,350,000 | Seattle | Washington | Seattle, WA | View → |
| King | 270 | Guthrie | Texas | Wichita Falls, TX | View → |
| King and Queen | 7,100 | Shacklefords | Virginia | Richmond, VA | View → |
| King George | 27,000 | King George | Virginia | Washington, DC | View → |
| King William | 17,000 | West Point | Virginia | Richmond, VA | View → |
| Kingfisher | 16,000 | Kingfisher | Oklahoma | Oklahoma City, OK | View → |
| Kingman | 7,500 | Kingman | Kansas | Wichita, KS | View → |
| Kings | 152,000 | Hanford | California | Fresno, CA | View → |
| Kings | 2,700,000 | Brooklyn | New York | New York, NY | View → |
| Kingsbury | 5,300 | De Smet | South Dakota | Sioux Falls-Rapid City, SD | View → |
| Kinney | 3,100 | Brackettville | Texas | San Antonio-Corpus Christi, TX | View → |
| Kiowa | 1,400 | Eads | Colorado | Denver-Colorado Springs, CO | View → |