| Kaarmise 719 borehole | Estonia | 58.3N, 22.3E | 2 | 56 | 137 | 93 | |
| Kaasiksaare F-8 borehole | Estonia | 59.4N, 27.7E | 6 | 3 | 2 | 2 | |
| Käesla 702 borehole | Estonia | 58.3N, 22.2E | 4 | 20 | 0 | 0 | |
| Kaavi 568 borehole | Estonia | 58.0N, 22.2E | 3 | 13 | 38 | 30 | |
| Kaavi 571 borehole | Estonia | 58.0N, 22.2E | 9 | 12 | 50 | 165 | |
| Kabala borehole, Lääne-Virumaa | Estonia | 59.4N, 26.6E | 6 | 1 | 2 | 2 | |
| Kaberla F-123 borehole | Estonia | 59.5N, 25.3E | 5 | 0 | 21 | 21 | |
| Kabila F-316 borehole | Estonia | 59.2N, 24.4E | 7 | 11 | 21 | 21 | |
| Kabuna K80 borehole | Estonia | 58.7N, 22.5E | 0 | 0 | 0 | 0 | |
| Agama 658 borehole | Estonia | 58.3N, 22.0E | 0 | 0 | 0 | 0 | |
| Kadila F-251 borehole | Estonia | 59.2N, 26.3E | 9 | 3 | 114 | 202 | |
| Kaagvere 1 borehole | Estonia | 58.3N, 26.9E | 40 | 729 | 432 | 400 | |
| Juminda 6 borehole | Estonia | 59.6N, 25.5E | 7 | 0 | 13 | 13 | |
| Jaagarahu borehole | Estonia | 58.4N, 22.0E | 6 | 90 | 95 | 107 | |
| Jaagarahu 24 borehole | Estonia | 58.4N, 22.0E | 0 | 0 | 0 | 0 | |
| Jaagarahu 699 borehole | Estonia | 58.4N, 22.0E | 0 | 0 | 9 | 8 | |
| Jaagarahu 867 borehole | Estonia | 58.4N, 22.0E | 0 | 0 | 0 | 0 | |
| Jaama 3 borehole | Estonia | 59.0N, 27.7E | 16 | 91 | 278 | 354 | |
| Jaanika F-319 borehole | Estonia | 59.2N, 24.3E | 2 | 0 | 12 | 11 | |
| Jakšiai 104 borehole | Lithuania | 55.2N, 23.7E | 4 | 56 | 70 | 66 | |
| Jalukse F-347 borehole | Estonia | 59.0N, 23.8E | 3 | 1 | 13 | 9 | |
| Järise 689 borehole | Estonia | 58.5N, 22.4E | 0 | 0 | 0 | 0 | |
| Järise 891 borehole | Estonia | 58.5N, 22.4E | 0 | 0 | 0 | 0 | |
| Jašiunai 586 borehole | Lithuania | | 1 | 0 | 14 | 11 | |
| Yashchera 8 borehole | Russia | 58.9N, 29.8E | 0 | 0 | 62 | 55 | |
