| Locality | Postal Code |
|---|---|
| Braddan, Douglas | IM4 |
| Castleward, Douglas | IM4 5EJ |
| Cooil, Douglas | IM4 2AQ, IM4 2AG |
| Cronkbourne, Douglas | IM4 |
| Douglas, Douglas | IM1, IM2, IM4 |
| Kewaigue, Douglas | IM2, IM4 |
| Mount Murray, Douglas | IM4 |
| Mount Rule, Douglas | IM4 |
| Port Soderick, Douglas | IM4 |
| Strang, Douglas | IM4 |
| Tromode, Douglas | IM4 4QD, IM4 4RG, IM4 … |