| Locality | Post Code |
|---|---|
| Huntshieldford | DL13 1RQ |
| Hunwick | DL15 |
| Hutton Henry | TS27 |
| Hutton Magna | DL11 |
| Ingleton | DL2 |
| Ireshopeburn | DL13 |
| Iveston | DH8 |
| Kelloe | DH6 |
| Kimblesworth | DH2 |
| Kinninvie | DL12 |
| Kip Hill | DH9 |
| Kirk Merrington | DL16 |
| Knitsley | DH8 |
| Lambton Park | DH3 |
| Lanchester | DH7 |
| Lanehead | DL13 |
| Langley Moor | DH7 |
| Langley Park | DH7 |
| Langleydale | DL12 |
| Langton | DL2 |
| Lartington | DL12 |
| Leadgate | DH8 |
| Leamside | DH4 |
| Leasingthorne | DL14 |
| Leeholme | DL14 |
| Lintz Green | NE39 |