Exchanges
| Code | Name |
|---|---|
| NIAFN | Aughafatten |
| NIAN | Aughnacloy |
| LVAUG | Aughton Green |
| WSAUL | Auldgirth |
| NSALB | Aultbea |
| NSALG | Aultguish |
| SSAVY | Avebury |
| NSAVI | Aviemore |
| ESAVO | Avonbridge |
| SSAVO | Avonmouth |
| SSAXB | Axbridge |
| WWAXMI | Axminster |
| NEAYC | Aycliffe |
| SMAY | Aylesbury |
| NDAYL | Aylesford |
| EMAYLES | Aylestone |
| EAAYL | Aylsham |
| WSAYR | Ayr |
| NEASG | Aysgarth |
| ESAYT | Ayton |
| NSBAC | Back |
| EABAC | Bacton |
| LCBAC | Bacup |
| NSBAD | Badachro |
| EABAD | Badingham |
| SSBAD | Badminton |
| WMBAD | Badsey |
| THBA | Bagshot |
| EMBGWOR | Bagworth |
| NIBMS | Baillies Mills |
| NEBNG | Bainbridge |
| EMBAINT | Bainton |
| EMBAKEW | Bakewell |
| WNBAL | Bala |
| NSBLL | Balallan |
| ESBLB | Balbeggie |
| SLBAL | Balby |
| SDBLCMB | Balcombe |
| SMBC | Baldock |
| NDBAL | Baldslow |
| WSBAL | Balfron |
| LSBAL | Balham |
| NSBCS | Ballachulish |
| WSBAE | Ballantrae |
| NSBLT | Ballater |
| NIBL | Ballinamallard |
| NIBK | Ballinaskeagh |
| NSBLD | Ballindalloch |
| ESBLY | Ballingry |
| ESBLG | Ballinluig |