S
- (Province of Cagayan) Sanja
- (Province of Cagayan) Sinago Island
- (Province of Cagayan) Santa Maria
- (Province of Isabela) Surcoc
- (Province of Batanes) Sumnanga
- (Province of Nueva Vizcaya) Sugag
- (Province of Isabela) Sucat
- (Province of Isabela) Spires Island
- (Province of Cagayan) Sarongan
- (Province of Batanes) Songsong
- (Province of Isabela) Songsong
- (Province of Cagayan) Siuan
- (Province of Cagayan) Sisim
- (Province of Isabela) Sisim Alto
- (Province of Cagayan) Sirit
- (Province of Isabela) Sipay
- (Province of Isabela) Sinsayon
- (Province of Cagayan) Sinungan
- (Province of Isabela) Sinippil
- (Province of Isabela) Sinili
- (Province of Cagayan) Sinicquing
- (Province of Cagayan) Singayan
- (Province of Isabela) Sindun Lupigi
- (Province of Isabela) Sinappil
- (Province of Nueva Vizcaya) Sinapawan
- (Province of Isabela) Sinaoangan Sur
- (Province of Isabela) Sinaoangan Norte
- (Province of Isabela) Sinamar Norte
- (Province of Isabela) Sinamar Sur
- (Province of Isabela) Sinalugan