- A423 between A445 and A45, Warwickshire (Grid ref SP371751)
- A423 between A445 and A45, Warwickshire (Grid ref SP380739)
- A423 between B4453 and A445, Warwickshire (Grid ref SP400710)
- A423 between A426 and B4453 Leamington Rd, Warwickshire (Grid ref SP416649)
- A423 between A425W and A425E, Warwickshire (Grid ref SP420614)
- A423 between A425 and A426, Warwickshire (Grid ref SP420626)
- A423 between Warwickshire boundary and A425, Warwickshire (Grid ref SP436520)
- A423 between A422 and Oxfordshire boundary, Oxfordshire (Grid ref SP449460)
- A423 between A34(T) and Abingdon Rd, Oxfordshire (Grid ref SP514035)
- A423 between A34(T) and Abingdon Rd, Oxfordshire (Grid ref SP516035)
- A423 between Abingdon Rd and A4144, Oxfordshire (Grid ref SP519035)
- A423 between A4142 / A4074 Heyford hill and A4144, Oxfordshire (Grid ref SP527030)