| Slavka | | - | Slovene, Croatian | |
| Slavko | | - | Croatian, Serbian, Slovene | |
| Sonja | | ZAWN-yah (German), SON-yah (Finnish) | German, Dutch, Swedish, Norwegian, Danish, Icelandic, Finnish, Slovene, Serbian, Croatian, Macedonia | |
| SreČKo | | - | Slovene | |
| StaŠA | | - | Serbian, Slovene, Croatian | |
| Stane | | - | Slovene | |
| Stanislav | | stah-nee-SLAHF (Russian) | Czech, Slovak, Russian, Ukrainian, Bulgarian, Slovene, Serbian, Croatian, Medieval Slavic | |
| Stanislava | | stah-nee-SLAH-vah (Russian) | Czech, Slovak, Bulgarian, Serbian, Croatian, Slovene, Russian, Medieval Slavic | |
| Stanka | | - | Slovene, Croatian, Bulgarian | |
| Stanko | | STAHN-ko (Slovene, Croatian) | Slovene, Croatian, Serbian, Bulgarian | |
| Stojan | | - | Macedonian, Serbian, Croatian, Slovene | |
| Suzana | | - | Croatian, Serbian, Slovene, Macedonian, Portuguese (Brazilian) | |