| Celebration | Name | Saint | Birth | Death |
|---|---|---|---|---|
| 1 of December | Clementina | Blessed Clementine Nengapeta Anuarite | 1939 Congo | 1964 Congo |
| 1 of December | Casimiro | Blessed Casimir Sykulski | 1882 Poland | 1941 Poland |
| 1 of December | Cándida | Saint Cándida | ||
| 1 of December | Carlos | Blessed Charles of Foucauld | 1858 France | 1916 Algeria |
| 2 of December | Constantine | Saint Constantine abbot | ||
| 3 of December | Cassian | Saint Cassian of Tangier | Mauritania | 300 Mauritania |
| 3 of December | Claudius tribune | Saint Claudius tribune | ||
| 3 of December | Crispin | Saint Crispin martyr | ||
| 5 of December | Crispina | Saint Crispina Tagorense | 304 | |
| 5 of December | Crispin | Saint Crispin | ||
| 8 of December | Constantino | Blessed Constantine Abbot | ||
| 9 of December | Cyprian | Saint Cyprian | France | France |
| 12 of December | Conrado | Blessed Conrado of Ofida | Italy | 1306 Italy |
| 12 of December | Corentinus | Saint Corentinus | France | France |
| 15 of December | Cristiana | Saint Cristiana | ||
| 15 of December | Carlos | Blessed Charles Steeb | Germany | 1856 Germany |
| 16 of December | Clemente | Blessed Clemente Marchisio | Italy | 1903 Italy |
| 17 of December | Christopher | Saint Christopher of Collesano | ||
| 17 of December | Cincuenta | Saints cincuenta soldados | Israel | 638 Israel |
| 28 of December | Catalina | Blessed Catalina Volpicelli | 1894 Italy | |
| 31 of December | Columba | Saint Columba virgen y mártir | France |