| Serafino | | - | Italian | |
| Serena | | sə-REEN-ə (English), se-RE-nah (Italian) | English, Italian, Late Roman | |
| Sergio | | SER-jo (Italian), SER-khyo (Spanish) | Italian, Spanish | |
| Sesto | | - | Italian | |
| Settimio | | - | Italian | |
| Severiano | | se-ve-RYAH-no | Italian, Spanish | |
| Severina | | - | Italian, Portuguese, Croatian, German, Ancient Roman | |
| Severino | | se-ve-REE-no (Italian, Spanish) | Italian, Spanish, Portuguese | |
| Severo | | se-VE-ro | Italian, Spanish | |
| Sibilla | | - | Italian | |
| Sigfrido | | seeg-FREE-do (Italian), seeg-FREE-dho (Spanish) | Italian, Spanish | |
| Silvana | | seel-VAH-nah | Italian | |
| Silvano | | seel-VAH-no | Italian | |
| Silvestra | | - | Italian, Slovene | |
| Silvestro | | seel-VE-stro | Italian | |