CB
16 districts, 11,227 postcodes
South Cambridgeshire, Cambridge, East Cambridgeshire, West Suffolk, Uttlesford, Braintree, and others
| District | Postcodes | Local authority |
|---|---|---|
| CB1 | 1,158 | Cambridge |
| CB10 | 576 | Uttlesford |
| CB11 | 551 | Uttlesford |
| CB2 | 587 | Cambridge |
| CB21 | 446 | South Cambridgeshire |
| CB22 | 610 | South Cambridgeshire |
| CB23 | 884 | South Cambridgeshire |
| CB24 | 816 | South Cambridgeshire |
| CB25 | 422 | East Cambridgeshire |
| CB3 | 411 | Cambridge |
| CB4 | 905 | Cambridge |
| CB5 | 279 | Cambridge |
| CB6 | 922 | East Cambridgeshire |
| CB7 | 746 | East Cambridgeshire |
| CB8 | 1,072 | West Suffolk |
| CB9 | 842 | West Suffolk |