- Alonzo
- Alpine
- Alta
- Altamont
- Altgeld Gardens
- Altmar
- Altorf
- Alworth
- Amenia
- Ament Corners
- America
- Ames
- Amity
- Anand Brook
- Ancient Tree
- Ancona
- Andalusia Island
- Anderson
- Anderson
- Andres
- Andrew
- Andrews and Hurds Subdivision
- Anetsberger's Subdivision
- Angelo Towhead
- Annapolis
- Anns Mobile Home Park
- Appaloosa West
- Apple Canyon Lake
- Apple River Island
- Applegate