- A404 between A4130 and Hurley Lane, Windsor and Maidenhead (Grid ref SU841830)
- A404 between A4130 and A4130, Windsor and Maidenhead (Grid ref SU843821)
- A404 between A404 main route and A4130, Windsor and Maidenhead (Grid ref SU843818)
- A404 between A4130 and Hurley Lane, Windsor and Maidenhead (Grid ref SU843836)
- A404 between Hurley Lane and A308, Windsor and Maidenhead (Grid ref SU846840)
- A404 between A404M and A4130, Windsor and Maidenhead (Grid ref SU850813)
- A404 between A308 and Windsor and Maidenhead boundary, Windsor and Maidenhead (Grid ref SU853850)
- A404 between A4155 and M40, Buckinghamshire (Grid ref SU857900)
- A404 between A4 and A404M, Windsor and Maidenhead (Grid ref SU857808)
- A404 between A4 and A404, Windsor and Maidenhead (Grid ref SU857808)
- A404 between M40 and A404 intersection, Buckinghamshire (Grid ref SU860920)
- A404 between Buckinghamshire boundary and A4155, Buckinghamshire (Grid ref SU862868)
- A404 between A404 intersection and A404, Buckinghamshire (Grid ref SU867928)
- A404 between B474 and Inkerman Drive, Hazelmere, Buckinghamshire (Grid ref SU873940)
- A404 between J9A and J9B, Windsor and Maidenhead (Grid ref SU874797)
- A404 between M4 and J9A, Windsor and Maidenhead (Grid ref SU881792)
- A404 between Inkerman Drive and A413, Buckinghamshire (Grid ref SU900960)
- A404 between A355 and A404 Woodside Rd roundabout, Buckinghamshire (Grid ref SU970971)
- A404 between A404 Woodside Rd roundabout and Church Grove, Little Chalfont, Buckinghamshire (Grid ref TQ000977)
- A404 between Church Grove, Little Chalfont and Buckinghamshire boundary, Buckinghamshire (Grid ref TQ010978)
- A404 between Hertfordshire boundary and road from North Hill, Hertfordshire (Grid ref TQ026975)
- A404 between road from North Hill, Chorleywood and M25, Hertfordshire (Grid ref TQ033967)
- A404 between M25 and A412, Hertfordshire (Grid ref TQ050958)
- A404 between A412 and A4145, Hertfordshire (Grid ref TQ060940)
- A404 between A4145 and Hertfordshire boundary, Hertfordshire (Grid ref TQ070928)
- A404 between Hillingdon boundary and A4180, Hillingdon (Grid ref TQ080919)
- A404 between A4180 and A4125, Hillingdon (Grid ref TQ090909)
- A404 between A4125 and Hillingdon boundary, Hillingdon (Grid ref TQ100906)
- A404 between Harrow boundary and Elm Park Rd, Harrow (Grid ref TQ110901)
- A404 between Elm Park Rd and A410, Harrow (Grid ref TQ120906)
- A404 between A410 and Headstone Lane, Harrow (Grid ref TQ131900)
- A404 between Headstone Lane and A4090, Harrow (Grid ref TQ135890)
- A404 between A4090 and A4005, Harrow (Grid ref TQ140884)
- A404 between A312 and A4005, Harrow (Grid ref TQ149880)
- A404 between A312 and B458, Harrow (Grid ref TQ153878)
- A404 between B458 and A409/A4006 roundabout, Harrow (Grid ref TQ160879)
- A404 between A409 and A4127, Brent (Grid ref TQ164869)
- A404 between A4127 and A4088, Brent (Grid ref TQ165862)
- A404 between A4088 and A4005, Brent (Grid ref TQ165860)
- A404 between A4005 and A4005, Brent (Grid ref TQ169852)
- A404 between A4005 and A4089, Brent (Grid ref TQ174850)
- A404 between A4089 and A4089, Brent (Grid ref TQ182851)
- A404 between A4089 and A4179, Brent (Grid ref TQ187852)
- A404 between A4179 and A406, Brent (Grid ref TQ191850)
- A404 between A406 and A407, Brent (Grid ref TQ200841)
- A404 between A407 and A404 split, Brent (Grid ref TQ213837)
- A404 between A4000 and A404 Manor Park Road, Brent (Grid ref TQ215835)
- A404 between A404 Craven Park Road and A404 High Street Harlesden, Brent (Grid ref TQ216835)
- A404 between A4000 Station Rd and A404 Manor Park Road, Brent (Grid ref TQ217833)
- A404 between A404 Manor Park Road and Tubbs Road, Brent (Grid ref TQ220832)
- A404 between Tubbs Road and A219, Brent (Grid ref TQ222830)
- A404 between A219 and La Boundary, Brent (Grid ref TQ229827)
- A404 between Westminster boundary and A4207, Westminster (Grid ref TQ240824)
- A404 between A4207 and A40, Westminster (Grid ref TQ250820)