| Locality | Post Code |
|---|---|
| Penrhosgarnedd, Gwynedd | LL57 |
| Penrhyn Park, Gwynedd | LL57 4HW |
| Penrhyndeudraeth, Gwynedd | LL48 |
| Pentir, Gwynedd | LL57 |
| Pentre Castell, Gwynedd | LL55 4UB |
| Pentre Uchaf, Gwynedd | LL53 |
| Pentrefelin, Gwynedd | LL52 |
| Penygroes, Gwynedd | LL54 |
| Pistyll, Gwynedd | LL53 |
| Plas Gwyn, Gwynedd | LL53 |
| Pontllyfni, Gwynedd | LL54 |
| Pontrug, Gwynedd | LL55 |
| Porthmadog, Gwynedd | LL49 |
| Prenteg, Gwynedd | LL49 |
| Pwllheli, Gwynedd | LL53 |
| Rachub, Gwynedd | LL57 3EJ |
| Rhiw, Gwynedd | LL53 |
| Rhiwbryfdir, Gwynedd | LL41 |