| Place | Postal Code |
|---|---|
| Leavesden, East of England) | WD25 |
| Watford, East of England) | WD17, WD18, WD24, WD25 |
| Postal Codes in Hertfordshire | |
|---|---|
| Broxbourne | |
| Dacorum | |
| East Hertfordshire | |
| Hertsmere | |
| North Hertfordshire | |
| St. Albans | |
| Stevenage | |
| Three Rivers | |
| Watford | |
| Welwyn Hatfield | |