| Kaelin | 1 |
| Kaidy | 1 |
| Kaiser | 3 |
| Kalb | 8 |
| Kaley | 3 |
| Kalinowski | 1 |
| Kappelman | 2 |
| Karabogias | 1 |
| Karasiewicz | 1 |
| Karem | 1 |
| Karnes | 2 |
| Karr | 1 |
| Kaster | 1 |
| Katie | 2 |
| Kauffman | 10 |
| Kay | 14 |
| Kayler | 1 |
| Kayman | 1 |
| Kearney | 1 |
| Kearsley | 2 |
| Keating | 2 |
| Kee | 1 |
| Keegan | 1 |
| Keeling | 3 |
| Keen | 5 |
| Keenan | 1 |
| Keene | 1 |
| Keeney | 1 |
| Kehloe | 1 |
| Keiningham | 1 |
| Keith | 2 |
| Keithley | 1 |
| Keller | 3 |
| Kellett | 2 |
| Kelley | 1 |
| Kellogg | 4 |
| Kelly | 22 |
| Kelsey | 1 |
| Kelton | 1 |
| Kemp | 20 |
| Kemper | 2 |
| Kempher | 1 |
| Kempson | 1 |
| Kenakis | 1 |
| Kendall | 3 |
| Kendrick | 1 |
| Kennedy | 13 |
| Kennerly | 1 |
| Kenney | 1 |
| Kent | 1 |
| Kerby | 1 |
| Kern | 9 |
| Kerr | 3 |
| Kersey | 1 |
| Kesterson | 2 |
| Kettler | 1 |
| Key | 8 |
| Keyes | 1 |
| Kidwell | 1 |
| Kiefer | 1 |
| Kilby | 2 |
| Kiley | 1 |
| Killick | 1 |
| Kilpatrick | 2 |
| Kimball | 1 |
| Kimbell | 3 |
| Kimberly | 2 |
| Kimmel | 5 |
| Kimmett | 2 |
| Kimrey | 1 |
| Kincaid | 1 |
| Kinder | 1 |
| King | 32 |
| Kingsbery | 1 |
| Kingsbury | 1 |
| Kinlaw | 1 |
| Kinnear | 2 |
| Kinney | 3 |
| Kinnison | 1 |
| Kinsella | 5 |
| Kintis | 2 |
| Kirby | 4 |
| Kirchem | 7 |
| Kirk | 1 |
| Kirkpatrick | 6 |
| Kirshman | 1 |
| Kissler | 1 |
| Kite | 2 |
| Klaas | 1 |
| Klawitter | 1 |
| Klentnauer | 1 |
| Kline | 3 |
| Klingenberger | 3 |
| Klingman | 1 |
| Kloess | 1 |
| Klyce | 1 |
| Knight | 13 |
| Knowles | 6 |
| Knox | 2 |
| Koch | 5 |
| Kochenderfer | 5 |
| Kocker | 1 |
| Koelling | 1 |
| Koenig | 1 |
| Kolaczkowski | 1 |
| Kraettli | 1 |
| Krall | 4 |
| Kramer | 1 |
| Kravitz | 1 |
| Krebs | 22 |
| Krepps | 1 |
| Kress | 1 |
| Kroboth | 1 |
| Krueger | 2 |
| Kunze | 2 |
| Kurruo | 1 |
| Kurtz | 3 |
| Kyle | 3 |
updated - GMB 06/16/07