| P | Surrey |
| PA | Guildford |
| PB | Guildford |
| PC | Guildford |
| PD | Guildford |
| PE | Guildford |
| PF | Guildford |
| PG | Guildford |
| PH | Guildford |
| PJ | Guildford |
| PK | Guildford |
| PL | Guildford |
| PM | Guildford |
| PN | Brighton |
| PO | Portsmouth (GPO formerly used for General Post Office vehicles) |
| PP | Luton (Buckinghamshire until 1974) |
| PR | Bournemouth |
| PS | Aberdeen (Lerwick until 1980) |
| PT | Newcastle upon Tyne (Durham until 1981) |
| PU | Chelmsford |
| PV | Ipswich |
| PW | Norwich |
| PX | Portsmouth |
| PY | Middlesbrough (Yorkshire (North Riding) until 1974) |