SO - Southampton
The postal area SO (Southampton) comprises of the following post towns; these towns should be written in capital letters when used in addresses.
Postal Districts within SO - Southampton
| Country | Post Town | Postal District |
| England | Southampton | SO14 SO15 SO16 SO17 SO18 SO19 |
| Stockbridge | SO20 | |
| Winchester | SO21 SO22 SO23 |
|
| Alresford | SO24 | |
| Southampton | SO30 SO31 SO40 |
|
| Lymington | SO41 | |
| Brockenhurst | SO42 | |
| Lyndhurst | SO43 | |
| Eastleigh | SO50 | |
| Romsey | SO51 SO52 |
|
| Eastleigh | SO53 |
