Samuil | | sah-moo-EEL (Russian) | Russian, Bulgarian | |
Sashka | | - | Macedonian, Bulgarian | |
Sasho | | - | Macedonian, Bulgarian | |
Sava | | - | Serbian, Bulgarian | |
Sergei | | syer-GYAY (Russian), seer-GYAY (Russian) | Russian, Bulgarian | |
Sergej | | syer-GYAY (Russian), seer-GYAY (Russian) | Russian, Bulgarian | |
Sergey | | syer-GYAY (Russian), seer-GYAY (Russian) | Russian, Bulgarian | |
Silva | | - | Bulgarian, Slovene | |
Silviya | | - | Bulgarian | |
Simeon | | SIM-ee-ən (English) | Biblical, Bulgarian, Serbian | |
Simona | | - | Italian, Czech, Slovak, Romanian, Lithuanian, Slovene, Bulgarian, Macedonian | |
Snezhana | | - | Russian, Bulgarian, Macedonian | |
Sofiya | | sah-FEE-yah (Russian) | Russian, Ukrainian, Bulgarian | |
Spartak | | - | Russian, Ukrainian, Bulgarian, Albanian, Armenian, Georgian | |
Spas | | - | Bulgarian | |