- A503 between Parkway and Camden High St, Camden (Grid ref TQ289836)
- A503 between Kentish Town Rd and Bayham St, Camden (Grid ref TQ289839)
- A503 between Bayham St and A400, Camden (Grid ref TQ290839)
- A503 between Camden High St and Camden Rd, Camden (Grid ref TQ290838)
- A503 between A400 and A5202, Camden (Grid ref TQ291841)
- A503 between A5202 and St Pancras Way, Camden (Grid ref TQ292842)
- A503 between St Pancras Way and Camden Park Rd, Camden (Grid ref TQ295846)
- A503 between Camden Park Rd and A5200, Camden (Grid ref TQ297849)
- A503 between A5200 and A5203, Islington (Grid ref TQ299852)
- A503 between A5203 and A1, Islington (Grid ref TQ302857)
- A503 between A5203 and A1/A5203, Islington (Grid ref TQ305857)
- A503 between A1 and A103, Islington (Grid ref TQ306861)
- A503 between A1/A5203 and A103, Islington (Grid ref TQ307858)
- A503 between A103 Hornsey rd and A503 Seven Sisters rd, Islington (Grid ref TQ310860)
- A503 between A103 Hornsey rd and A503 Isledon Rd, Islington (Grid ref TQ310864)
- A503 between Isledon Rd and Stroud Green Rd/Blackstock Rd, Islington (Grid ref TQ313867)
- A503 between A1201 and A105, Hackney (Grid ref TQ320874)
- A503 between A105 and A107, Hackney (Grid ref TQ325877)
- A503 between A107 and Hackney boundary, Hackney (Grid ref TQ327879)
- A503 between Haringey boundary and A10, Haringey (Grid ref TQ330884)
- A503 between A10 and A1055, Haringey (Grid ref TQ340890)
- A503 between A1055 and Haringey boundary, Haringey (Grid ref TQ346894)
- A503 between Waltham Forest boundary and A1006, Waltham Forest (Grid ref TQ350893)
- A503 between A1006 and A112, Waltham Forest (Grid ref TQ360894)
- A503 between A112 Chingford Road and A104 Woodford New Road, Waltham Forest (Grid ref TQ383900)