| SURNAME | TOWNSHIP | RESEARCHER |
| Kapp/Capp | Alan Weaver | |
| Keeling | Charlotte Lucas | |
| Keil | Brenda | |
| Kellogg | Laurie | |
| Kelly | Libertyville; 1844-1857 | Catherine Green |
| Kernebeck/Kennebeck | Marv Kennebeck | |
| Kerr | Laurie | |
| Kershinar |
1904- |
Jody Miller |
| Kilbane | Fremont & Waukegan | Cathy Sheehan |
| Kiple
website |
Zion | Sandy Bressler |
| Kirk | Waukegan | Kathy |
| Klein | Don Finel | |
| Klingberg | Ela - 1857 | Diane Strothers |
| Klump | Waukegan - after 1900 | mjnole |
| Knutson | Sandy Demlow | |
| Koch | Glencoe | Linda Greenleaf |
| Koepsel | Aly Koepsel | |
| Koivula | Waukegan after 1925 | John Small |
| Koller | Brenda | |
| Koziol | Janice Lynn | |
| Kriesel
website |
Waukegan | Andrea Gibbons |
| Krueger | Rockefeller, now Hawthorn Woods/Libertyville area | Jodi Rychlik |
| Krueger
website |
Waukegan | Andrea Gibbons |
| Kruger | MMVINDY1 | |
| Kufahl | Waukegan |
TONILYNNR@cs.com |
| Kuntz (Kunt) | Thelma Kubicek Reukauf | |
| Kureger | Marilynn Wienke |