C
- (Province of Cagayan) Cataliganan
- (Province of Cagayan) Calapangan Norte
- (Province of Cagayan) Centro East
- (Province of Cagayan) Centro West
- (Province of Cagayan) Capanickian Norte
- (Province of Cagayan) Cabayabasan
- (Province of Cagayan) Centro Sur
- (Province of Cagayan) Centro Norte
- (Province of Cagayan) Centro West
- (Province of Cagayan) Centro East
- (Province of Isabela) Calinaoan Malasin
- (Province of Isabela) Calinauan
- (Province of Isabela) Cabannungan Second
- (Province of Cagayan) Calaoagan
- (Province of Cagayan) Calantac
- (Province of Isabela) Calamagui East
- (Province of Isabela) Calamagui
- (Province of Isabela) Cabulay
- (Province of Cagayan) Capissayan Sur
- (Province of Cagayan) Carig
- (Province of Cagayan) Cabiraoan
- (Province of Cagayan) Calog Norte
- (Province of Cagayan) Casambalangan
- (Province of Cagayan) Catayauan
- (Province of Isabela) Cullalabo del Sur
- (Province of Quirino) Cabarroguis
- (Province of Cagayan) Cabaritan West