A
- (Province of Ilocos Sur) Ayusan Sur
- (Province of Ilocos Sur) Ayusan Norte
- (Province of Ilocos Sur) Ayudante
- (Province of La Union) Ayaoan
- (Province of Pangasinan) Awag
- (Province of Pangasinan) Austria
- (Province of Pangasinan) Awile
- (Province of Ilocos Norte) Atimon
- (Province of La Union) Atic
- (Province of Pangasinan) Atel
- (Province of Pangasinan) Ataynan
- (Province of Ilocos Sur) Atabay
- (Province of Ilocos Norte) Assace
- (Province of Ilocos Sur) Asin
- (Province of Pangasinan) Asinda
- (Province of Ilocos Sur) Asilang
- (Province of Ilocos Sur) Asilang
- (Province of Pangasinan) Asan Sur
- (Province of Pangasinan) Asan Norte
- (Province of Ilocos Norte) Ayoyo
- (Province of Ilocos Norte) Arua-ay
- (Province of Pangasinan) Artacho
- (Province of Pangasinan) Arnedo
- (Province of Ilocos Sur) Arnap
- (Province of Pangasinan) Ariston Weste
- (Province of La Union) Areno Sur
- (Province of La Union) Areno Norte
- (Province of Pangasinan) Arsaas
- (Province of La Union) Ararampang
- (Province of Ilocos Norte) Ar-aro-o