3 Digits
| Road | From | To | Notes |
|---|---|---|---|
| B400 | A4 Fleet Street | A40 Holborn | Chancery Lane. One way only Northbound |
| B408 | A315 King Street, Hammersmith | A4020 Shepherd's Bush | Road Names: Dalling Road, Paddenswick Road, Askew Road |
| B409 | A402 Goldhawk Road, Stamford Brook | B490 at Acton Green | Road Names: Stamford Brook Road, Bath Road, South Parade |
| B412 | A219 Shepherds Bush | A4207 Notting Hill | To the West of Ladbroke Grove it follows North Pole Road, St Quentin Avenue, St Marks Road and Cambridge Gardens.
To the East, though Westbourne Park Road. Crosses Portobello Road. |
| B413 | A5 Maida Vale | B450 Chamberlayne Road | In two parts: Maida Vale to Kilburn Park Road, and Kilburn Park Road to Kensal Green. Via Warwick Avenue tube station. Road Names: Clifton Road, Clifton Gardens, Warwick Avenue, Formosa Street, Shirland Road, Carlton Vale, Kilburn Lane |
| B414 | A5 Maida Vale | A404 Harrow Road at Westbourne Green | Road Names: Kilburn Park Road, Walterton Road, Fernhead Road |
| B416 | A4 Wellington Street / A332 roundabout at Slough | A413 Amersham Road at Gerrards Cross | |
| B425 | A45 in Sheldon, West Midlands | A41 in Solihull | |
| B430 | A34 at Weston-on-the-Green | M40 at Ardley | |
| B450 | A402 at Holland Park | B451 at Kensal Rise | Much of this is Ladbroke Grove in Notting Hill and passes close to Portobello Road market. |
| B451 | A404 at Kensal Green | A5 at Kilburn | Via Kensal Green railway station. Road Names: College Road, Mortimer Road, Harvist Road, Brondesbury Road |
| B452 | A3002 at Brentford | A40 at Perivale | Via Brentford railway station, Northfields tube station and West Ealing railway station. Road Names: Windmill Road, Northfield Avenue, Drayton Green Road, Argyle Road, Teignmouth Gardens |
| B454 | A315 at Isleworth | A4127 at Southall | Via Syon Lane railway station, and crosses Osterley Park. Road Names: Spur Road, Syon Lane, Windmill Lane. |
| B455 | A315 at Brentford | A312/A4180 roundabout at Yeading | Via South Ealing tube station and Ealing Broadway railway station. Road Names: Ealing Road, South Ealing Road, Saint Mary's Road, Ealing Green, Bond Street, Ealing High Street, Ealing Broadway, Haven Green, Castlebar Road, Castlebar Hill, Kent Gardens, Scotch Common, Ruislip Road East, Greenford Broadway, Ruislip Road |
| B456 | A40 Western Avenue | A4005 at Alperton | Road Name: Alperton Lane |
| B457 | A4005 at Roxeth | A409 at Harrow | Via Harrow School and Harrow-on-the-Hill station. Road Names: London Road, Harrow High Street, Peterborough Road, Station Road |
| B462 | A411 at Bushey Arches | A5183 at Radlett | |
| B465 | A4020 at Hillingdon | A408 at Stockley Park | Road Name: West Drayton Road |
| B466 | A4020 at Hillingdon | A404 at Pinner | Via West Ruislip railway station. Road Names: Long Lane, Ickenham High Road, Ickenham Road, Eastcote Road, Eastcote High Road, Cuckoo Hill |
| B467 | A4020 at Uxbridge | B466 at Ickenham | Road Names: Harefield Road, Swakeleys Road |
| B469 | A404 at Northwood | A4215 at Northwood | Via Northwood tube station. Road Name: Green Lane |
| B470 | A408 at Cowley | A4 at Windsor | Via Langley railway station. |
| B471 | Pangbourne, Berkshire | A4074 at Woodcote, Oxfordshire | |
| B472 | A404 at Northwood Hills | B466 at Eastcote | Via Northwood Hills tube station. Road Name: Joel Street |
| B473 | A407 at Willesden | A4088 at Neasden | Via Neasden tube station. Road Name: Neasden Lane |
| B474 | A40 at Beaconsfield | A404 at Hazlemere | |
| B480 | A4130 Fair Mile, Henley-on-Thames | Iffley | |
| B481 | A4155 Caversham | B480 just south of Watlington | Connects Reading to B4009 at Watlington and hence the M40 2.5miles north of Watlington |
| B482 | A4155 Marlow | A40 Stokenchurch | By way of Lane End, Bolter End and Cadmore End |
| B483 | A4020 at Uxbridge | A40 at Ickenham | Road Name: Park Road |
| B485 | A416 at Chesham | A413 at Great Missenden | |
| B488 | Aston Clinton, Tring | A4146 south of Leighton Buzzard, | Begins at a grade separated junction east of Aston Clinton. |
| B489 | B4009 at Aston Clinton | A5/A505 at Dunstable | Formerly started on the A41, now crosses the bypassed A41 and starts in Aston Clinton on the B4009. |
| B490 | A315 at Chiswick | A4020 at Acton | Via Chiswick Park tube station. Road Names: Acton Lane, Beaconsfield Road, Acton Lane, Winchester Street |
| B491 | A315 at Chiswick | B490 near Acton | Via Turnham Green tube station. Road Names: Turnham Green Terrace, The Avenue, Southfield Road |
Read more about this topic: B Roads In Zone 4 Of The Great Britain Numbering Scheme