| Code | Name |
|---|---|
| WSACH | Achnamara |
| NSASN | Achnasheen |
| NSASC | Achnashellach |
| CMACK | Ackleton |
| EAACL | Acle |
| CMACO | Acocks Green |
| MYACO | Acomb |
| LWACT | Acton |
| WNAB | Acton Burnell |
| WMADB | Adbaston |
| SMAD | Adderbury |
| MYADD | Addingham |
| LSADD | Addiscombe |
| MYADE | Adel |
| LCADL | Adlington |
| NSADV | Advie |
| SLADK | Adwick Le Street |
| SWAEN | Aeron |
| NIAGH | Aghadowey |
| NIAL | Aghalee |
| NIAH | Ahoghill |
| LCAIN | Ainsdale |
| LVAIN | Aintree |
| WSAIR | Airdrie |
| ESAIR | Airth |
| MYAIR | Airton |
| LNADK | Albert Dock |
| CMALB | Albrighton |
| EAALB | Albury |
| CMALC | Alcester |
| SSABE | Aldbourne |
| MYALD | Aldbrough |
| SMAC | Aldbury Common |
| EAABR | Aldeburgh |
| EAABY | Aldeby |
| STALDBY | Alderbury |
| MRALD | Alderley Edge |
| CMALDM | Alderminster |
| THAD | Aldershot |
| SSADN | Alderton |
| WNAF | Aldford |
| NDALD | Aldington |
| CMALD | Aldridge |
| WSALE | Alexandria |
| NSALF | Alford Grampion |
| SLAF | Alford Lincs |
| EMALFRE | Alfreton |
| SDLFRST | Alfriston |
| NEALD | Allendale |
| NEALH | Allenheads |
