• Single digit motorways

    • M1, the eastern north-south motorway linking London and Leeds and continuing north to the A1.

    • M2, in Kent from Rochester to Faversham.

    • M3, linking Southampton and London.

    • M4, linking London and south Wales.

    • M5, linking Exeter and the south-west of England with Birmingham and the Midlands.

    • M6, the western north-south motorway linking the M1 at Rugby and Carlisle.

    • M6 Toll, a toll motorway bypassing a busy stretch of the M6 around North Birmingham.

    • M8, linking Edinburgh and Glasgow.

    • M9, linking Edinburgh and Stirling.

    • M1 (Northern Ireland) from Belfast to Dungannon.

    • M2 (Northern Ireland) from Belfast to Antrim, and again near Ballymena.

 

  • Two digit motorways

    • M10, a short spur from the M1 to St Albans.

    • M11, linking London and Cambridge.

    • M18, linking the M1 at Rotherham and the M62 at Goole, South Yorkshire.

    • M20, linking London (Swanley) and Folkstone.

    • M23, linking London (Coulsdon) to beyond Crawley.

    • M25, the London orbital motorway.

    • M26, a short link between the M25 at Sevenoaks and the M20 before Maidstone.

    • M27, the south coast route running from Cadnam, west of Southampton, to Portsmouth.

    • M32, a spur from the M4 to central Bristol.

    • M40, linking London and Birmingham and linking to the M42 Birmingham orbital motorway .

    • M42, The southern and eastern part of the Birmingham orbital motorway extending north towards Ashby-de-la-Zouch and west to the M5.

    • M45, a short spur from M1 north of Daventry towards Coventry.

    • M48, the Severn Bridge, linking Thornbury and Newport, Monmouthshire over the River Severn. This used to be the M4 before the Second Severn Crossing was built.

    • M49, a short link from M5 to M4 west of Bristol.

    • M50, linking the M5 at Tewkesbury to Ross-on-Wye.

    • M53, linking Chester and Birkenhead.

    • M54, linking M6 north of Wolverhampton and Telford.

    • M55, linking Blackpool and M6 at Preston.

    • M56, linking Manchester and Chester.

    • M57, a Liverpool bypass running north west from the M62.

    • M58, linking Wigan and northern Liverpool.

    • M60, the Manchester orbital motorway.

    • M61, linking Preston and Manchester.

    • M62, linking Liverpool and the approaches to Kingston-upon-Hull, the trans-Pennine link.

    • M65, linking Preston and Colne, Lancashire.

    • M66, linking Rawtenstall and M62 at Manchester.

    • M67, linking the M60 at Denton to Hyde in Greater Manchester.

    • M69, linking Leicester and Coventry.

    • M73, linking Cumbernauld to the M74.

    • M74, linking Glasgow and Abington in South Lanarkshire, where the A74(M) takes over.

    • M77, linking Glasgow and Newton Mearns.

    • M80, linking Glasgow and Stirling.

    • M90, linking the Forth Road Bridge and Perth, Scotland.

 

  • Three or more digit motorways and spurs

    • M180, from the M18 at Thorne towards Grimsby and the A15 to the Humber Bridge.

    • M181, the Scunthorpe spur from the M180.

    • M271, the Totton, Southampton spur from the M27

    • M275, the Portsmouth spur from the M27

    • M602, M62 spur into Manchester.

    • M606, M62 spur at Bradford.

    • M621, M62 spur at Leeds.

    • M876, a short link between motorways in the Falkirk area.

    • M898, the Erskine Bridge approach road.

 

  • Upgraded A-road designations

    • A1(M), representing the parts of the A1 road between London and Newcastle-upon-Tyne that have been upgraded to motorway.

    • A167(M) in central Newcastle-upon-Tyne.

    • A194(M) spur from the Newcastle-upon-Tyne stretch of the A1(M) running towards the Tyne Tunnel.

    • A3(M), a short stretch of the A3 road by-passing Waterlooville and Havant, that has been built to motorway standards.

    • A308(M), linking the M4 junction 8/9 with Maidenhead.

    • A329(M), linking Bracknell and Winnersh near Reading.

    • A38(M), a spur from the M6 to central Birmingham, also known as the Aston Expressway. It is unique in having no central reservation.

    • A404(M), linking the M4 junction 8/9 towards Henley-on-Thames.

    • A58(M) is the western part of the Leeds inner ring road.

    • A601(M) Spur off the M6 at Carnforth, Lancashire. The southern part is single carriageway.

    • A6144(M), the longest single-carriageway motorway spur in the United Kingdom from the M60 north of Sale towards Carrington

    • A64(M) is the eastern part of the Leeds inner ring road.

    • A66(M) is a short spur from the A1(M) to Darlington

    • A74(M), linking Abington in South Lanarkshire at the end of the M74 with Carlisle.

 

  • Roads which used to be motorways but have been downgraded

    • A18(M) Spur from M18. Mostly now part of M180, although a section has been abandoned.

    • A329(M) from Winnersh to Reading, now the A3290. Downgraded to permit Reading council to dedicate one lane for buses.

    • A40(M) London Westway, now the A40.

    • A41(M) Tring bypass, now the A41.

    • A46(M) Spur towards Leicester from M1 at junction 21.

    • M41 was a spur from the London Westway.

UK Motorways