| Cristiano | | kree-STYAH-no (Italian), kreesh-TYA-noo (Portuguese) | Italian, Portuguese | |
| Cristina | | kree-STEE-nah (Italian, Spanish) | Italian, Spanish, Portuguese, Romanian | |
| Cristoforo | | - | Italian | |
| Crocetta | | kro-CHET-tah | Italian | |
| Crocifissa | | kro-chee-FEE-sah | Italian | |
| Cruz | | KROOTH (Spanish), KROOS (Latin American Spanish), KROOSH (Portuguese) | Spanish, Portuguese | |
| Cruzita | | kroo-THEE-tah (Spanish), kroo-SEE-tah (Latin American Spanish) | Spanish | |
| Csaba | | CHAW-baw | Hungarian | |
| Csenge | | CHENG-ge | Hungarian | |
| Csilla | | CHEEL-law | Hungarian | |
| CuauhtÉMoc | | - | Native American, Nahuatl | |
| Cuidightheach | | - | Ancient Irish | |
| Cunigund | | - | Ancient Germanic | |
| Cunobelinus | | kyoo-no-bə-LIEN-əs (English) | Ancient Celtic | |
| Cupid | | KYOO-pəd (English) | Roman Mythology | |