A
- Aberarder
- Aberfeldy
- Aberfoyle
- Aberfoyle Creek Estates
- Abingdon
- Abitibi
- Abitibi 70
- Abitibi Canyon
- Abiwin
- Acanthus
- Achigan
- Achill
- Achray
- Actinolite
- Acton
- Actons Corners
- Adamsville
- Addington Highlands
- Addison
- Adelaide
- Adelaide Metcalfe
- Adelard
- Adjala-Tosorontio
- Admaston-Bromley
- Adolphustown
- Advance
- Agawa
- Agawa Bay
- Agency 1
- Agency Indian Reserve No. 30
- Agerton
- Agincourt North
- Agincourt South-Malvern West
- Agonzon
- Ahmic Harbour
- Ahmic Lake
- Aikensville
- Ailsa Craig
- Airlie
- Ajax
- Akron
- Akwesasne
- Akwesasne 59
- Alban
- Albany
- Albert
- Alberton
- Alberton, Hamilton Division
- Albion
- Albuna
- Albury
- Alcona
- Alden
- Alder
- Alderdale
- Aldershot
- Alderslea
- Alderville First Nation
- Alderwood
- Aldred's Beach
- Alert
- Alexandria
- Alfred
- Alfred and Plantagenet
- Alfred Station
- Algoma Mills
- Algoma, Unorganized, North Part
- Algoma, Unorganized, South East Part
- Algonquin
- Algonquin Highlands
- Algonquins Of Pikwàkanagàn
- Alice
- Allanburg
- Allan Mills
- Allan Park
- Allans Corners
- Allanwater
- Allanwater Bridge
- Allenford
- Allen's Corners
- Allensville
- Allenwood
- Allenwood Beach
- Alliance
- Allimil
- Allimill
- Allisonville
- Alliston
- Alloa
- Allsaw
- Alma
- Almira
- Almonte
- Alnwick/Haldimand
- Alpine Village
- Alport
- Alsace
- Alsfeldt
- Alsops Beach
- Althorpe
- Alton
- Altona
- Alva
- Alvanley
- Alvinston
- Amaranth
- Amaranth Station
- Ambassador Beach
- Amberley
- Ambleside
- Ambuoy
- Ameliasburg
- Amesdale
- Ameson
- Amethyst Harbour
- Amherstburg
- Amherst Pointe
- Amherstview
- Amiens
- Amigari Downs
- Amigo Beach
- Amik/Talisman
- Amulree
- Amwri
- Ancaster
- Ancliff
- Ancona Point
- Anderson Lake
- Andrewsville
- Andy's Corners
- Angling Lake
- Angus
- Anjigami
- Annable Settlement
- Annan
- Annex
- Annex, Thunder Bay District
- Anoma Lea
- Ansnorveldt
- Ansonia
- Ansonville
- Anstice
- Anstigo
- Anstruther Lake
- Anten Mills
- Anthony
- Antioch
- Antrim
- Appelo
- Appin
- Appleby Corner
- Applecroft
- Appledore
- Apple Hill
- Appleton
- Apsley
- Apto
- Arbor-Vitae
- Archer
- Ardbeg
- Arden
- Ardendale
- Ardmore Beach
- Ardoch
- Ardtrea
- Argolis
- Argon
- Argonaut
- Argyle
- Ariss
- Arkell
- Arklan
- Arkona
- Arkwood
- Arkwright
- Arlington
- Armour
- Armour Heights
- Armow
- Arms
- Armstrong
- Armstrong Mills
- Armstrongs Corners
- Armstrong Station
- Arner
- Arnprior
- Arnstein
- Aroland
- Aroland Indian Settlement
- Arpin
- Arran-Elderslie
- Arranvale
- Arthur
- Arthur's Corners
- Arva
- Ascalon
- Ash
- Ashburn
- Ashburton
- Ashby Mill
- Ashdad
- Ashfield-Colborne-Wawanosh
- Ashgrove
- Ashton
- Ashton Station
- Ashworth
- Asinka
- Aspdin
- Asphodel-Norwood
- Assabaska Indian Reserve
- Asselstine
- Assiginack
- Assumption
- Astorville
- Atha Road
- Athens
- Atherley
- Atherton
- Athlone
- Athol
- Atikokan
- Atikup
- Atironto
- Attawapiskat 91A
- Attawapiskat Indian Reserve No. 91
- Attercliffe
- Attercliffe Station
- Atwood
- Auburn
- Auden Park
- Audley
- Aughrim
- Augsburg
- Augusta
- Aunor
- Aurora
- Austin
- Avalon Park
- Avening
- Avery Point
- Avon
- Avonbank
- Avondale
- Avonmore
- Avonry
- Avonton
- Axe Lake
- Aylen
- Aylen Lake
- Aylen Lake Station
- Aylesworth
- Aylmer
- Ayr
- Ayton
- Azen
- Azilda