A
- (Province of Isabela) Amobocan
- (Province of Cagayan) Abariongan Ruar
- (Province of Nueva Vizcaya) Amelong Labeng
- (Province of Nueva Vizcaya) Ayom
- (Province of Isabela) Auitan
- (Province of Cagayan) Atulu
- (Province of Isabela) Atelong
- (Province of Nueva Vizcaya) Atbo
- (Province of Cagayan) Atayao
- (Province of Isabela) Asuacan
- (Province of Cagayan) Asassi
- (Province of Isabela) Assantu
- (Province of Cagayan) Asinga-Via
- (Province of Isabela) Asin Boji
- (Province of Isabela) Arusip
- (Province of Isabela) Arubub
- (Province of Cagayan) Araiat
- (Province of Cagayan) Aragao
- (Province of Cagayan) Aracat
- (Province of Isabela) Arabiat
- (Province of Isabela) Ara
- (Province of Cagayan) Aquiliquilao
- (Province of Cagayan) Aquib
- (Province of Cagayan) Apulagan Island
- (Province of Isabela) Apiat
- (Province of Cagayan) Apayao
- (Province of Isabela) Antatet-Kalinga
- (Province of Nueva Vizcaya) Antapoc
- (Province of Isabela) Antagan
- (Province of Isabela) Antaga