Stations
| Abbey Wood |
| Aber |
| Abercynon |
| Aberdare |
| Aberdeen |
| Aberdour |
| Aberdovey |
| Abererch |
| Abergavenny |
| Abergele and Pensarn |
| Aberystwyth |
| Accrington |
| Achanalt |
| Achnasheen |
| Achnashellach |
| Acklington |
| Acle |
| Acocks Green |
| Acton Bridge (Cheshire) |
| Acton Central |
| Acton Main Line |
| Adderley Park |
| Addiewell |
| Addlestone |
| Adisham |
| Adlington (Cheshire) |
| Adlington (Lancs) |
| Adwick |
| Aigburth |
| Ainsdale |
| Aintree |
| Airbles |
| Airdrie |
| Albany Park |
| Albrighton |
| Alderley Edge |
| Aldermaston |
| Aldershot |
| Aldrington |
| Alexandra Palace |
| Alexandra Parade |
| Alexandria |
| Alfreton |
| Allens West |
| Alloa |
| Alness |
| Alnmouth |
| Alresford (Essex) |
| Alsager |
| Althorne (Essex) |
| Althorpe |
| Altnabreac |
| Alton |
| Altrincham |
| Alvechurch |
| Ambergate |
| Amberley |
| Amersham |
| Ammanford |
| Ancaster |
| Anderston |
| Andover |
| Anerley |
| Angmering |
| Annan |
| Anniesland |
| Ansdell and Fairhaven |
| Apperley Bridge |
| Appleby |
| Appledore (Kent) |
| Appleford |
| Appley Bridge |
| Apsley |
| Arbroath |
| Ardgay |
| Ardlui |
| Ardrossan Harbour |
| Ardrossan South Beach |
| Ardrossan Town |
| Ardwick |
| Argyle Street |
| Arisaig |
| Arlesey |
| Armadale (West Lothian) |
| Armathwaite |
| Arnside |
| Arram |
| Arrochar and Tarbet |
| Arundel |
| Ascot (Berks) |
| Ascott-under-Wychwood |
| Ash |
| Ash Vale |
| Ashburys |
| Ashchurch for Tewkesbury |
| Ashfield |
| Ashford (Surrey) |
| Ashford International |
| Ashford International (Eurostar) |
| Ashley |
| Ashtead |
| Ashton-under-Lyne |
| Ashurst (Kent) |
| Ashurst New Forest |
| Ashwell and Morden |
| Askam |
| Aslockton |
| Aspatria |
| Aspley Guise |
| Aston |
| Atherstone |
| Atherton |
| Attadale |
| Attenborough |
| Attleborough |
| Auchinleck |
| Audley End |
| Aughton Park |
| Aviemore |
| Avoncliff |
| Avonmouth |
| Axminster |
| Aylesbury |
| Aylesbury Vale Parkway |
| Aylesford |
| Aylesham |
| Ayr |