Districts in the BB area
| District | Main place | Local authority | Sectors | Postcodes |
|---|---|---|---|---|
| BB1 | Blackburn | Blackburn with Darwen | 9 | 1,310 |
| BB2 | Blackburn | Blackburn with Darwen | 8 | 1,414 |
| BB3 | Darwen | Blackburn with Darwen | 5 | 931 |
| BB4 | Rawtenstall | Rossendale | 7 | 1,336 |
| BB5 | Accrington | Hyndburn | 8 | 1,552 |
| BB6 | Great Harwood | Hyndburn | 2 | 373 |
| BB7 | Clitheroe | Ribble Valley | 6 | 1,228 |
| BB8 | Colne | Pendle | 4 | 785 |
| BB9 | Nelson | Pendle | 7 | 1,397 |
| BB10 | Burnley | Burnley | 4 | 891 |
| BB11 | Burnley | Burnley | 6 | 840 |
| BB12 | Burnley | Burnley | 5 | 978 |
| BB18 | Barnoldswick | Pendle | 3 | 573 |