| Sonda F-225 borehole | Estonia | 59.3695, 26.8250 | 438 | 8 | 7 | 97 | 98 | |
| Soonda 843 borehole | Estonia | 58.5912, 23.2954 | 82.1 | 1 | 0 | 0 | 0 | |
| Soone F-344 borehole | Estonia | 58.9189, 23.9033 | 383 | 3 | 8 | 23 | 13 | |
| Soonlepa F-366 borehole | Estonia | 58.8489, 23.0087 | 369 | 4 | 5 | 96 | 89 | |
| Sootaguse H-113 borehole | Estonia | 59.0662, 24.7889 | | 2 | 4 | 35 | 35 | |
| Sootaguse F-131 borehole | Estonia | 59.3492, 26.0803 | 324.2 | 7 | 5 | 21 | 22 | |
| Soovälja K12 borehole | Estonia | 58.9810, 22.7843 | 458.6 | 5 | 0 | 14 | 14 | |
| Sirtsi F-193 borehole | Estonia | 59.2734, 26.9093 | 377.8 | 13 | 3 | 34 | 34 | |
| Sarve K160 borehole | Estonia | 58.8283, 23.0392 | 49.5 | 0 | 0 | 58 | 0 | |
| Saikla 831 borehole | Estonia | 58.5370, 22.9901 | 72.5 | 1 | 20 | 0 | 0 | |
| Saka 60 borehole | Estonia | 59.4360, 27.1970 | 237.3 | 4 | 0 | 1 | 1 | |
| Sakla borehole | Estonia | 58.3615, 22.8613 | 141.63 | 24 | 445 | 209 | 279 | |
| Saku borehole | Estonia | 59.3049, 24.6620 | 242.7 | 4 | 1 | 1 | 1 | |
| Sakusaare F-136 borehole | Estonia | 59.4700, 25.9654 | 306.7 | 10 | 6 | 107 | 123 | |
| Salmistu F-105 borehole | Estonia | 59.4894, 25.3294 | 218.8 | 5 | 0 | 8 | 8 | |
| Salutaguse F-289 borehole | Estonia | 59.1766, 24.8063 | 320.3 | 6 | 1 | 15 | 15 | |
| Salutaguse 1 borehole | Estonia | | 36.4 | 1 | 0 | 0 | 0 | |
| Sandla 922 borehole | Estonia | 58.3018, 22.8182 | 45.6 | 0 | 0 | 0 | 0 | |
| Sanniku F-10 borehole | Estonia | 59.3764, 27.5231 | 296.05 | 3 | 0 | 11 | 11 | |
| Sanniku F-17 borehole | Estonia | 59.3793, 27.5355 | 300 | 3 | 1 | 1 | 1 | |
| Siiksaare 928 borehole | Estonia | 58.3173, 22.8860 | 20 | 0 | 0 | 0 | 0 | |
| Sarapiku 794 borehole | Estonia | 58.4725, 21.9302 | 16.2 | 0 | 0 | 0 | 0 | |
| Shiupyliai 69 borehole | Lithuania | 56.0500, 23.0900 | | 8 | 0 | 85 | 37 | |
| Sasnava 6 borehole | Lithuania | 54.6521, 23.4550 | | 9 | 0 | 0 | 0 | |
| Saue borehole | Estonia | | | 1 | 0 | 0 | 0 | |
