| UB1 |
SOUTHALL |
Southall (north) |
Ealing |
| UB2 |
SOUTHALL |
Southall (south), Norwood Green |
Ealing |
| UB3 |
SOUTHALL |
|
non-geographic[3][4] |
| UB3 |
HAYES |
Hayes (south), Harlington |
Hillingdon |
| UB4 |
HAYES |
Hayes (north), Yeading |
Hillingdon |
| UB5 |
GREENFORD |
|
non-geographic[3][5] |
| UB5 |
NORTHOLT |
Northolt |
Ealing |
| UB6 |
GREENFORD |
Greenford, Perivale |
Ealing |
| UB7 |
WEST DRAYTON |
West Drayton, Harmondsworth, Sipson, Yiewsley, Longford |
Hillingdon |
| UB8 |
WEST DRAYTON |
|
non-geographic[3][6] |
| UB8 |
UXBRIDGE |
Uxbridge, Cowley, Hillingdon (part) |
Hillingdon |
| UB9 |
UXBRIDGE |
Denham, Harefield, Tatling End (east) |
Hillingdon, Buckinghamshire |
| UB10 |
UXBRIDGE |
Hillingdon, Ickenham |
Hillingdon |
| UB11 |
UXBRIDGE |
Stockley Park |
Hillingdon |
| UB18 |
GREENFORD |
Spring International |
non-geographic[3][7] |