M27

The M27 forms a bypass and distributor road for the urban sprawl along the south coast in Hampshire, from Portsmouth and Gosport to Southampton.

On the road, it often looks and feels every bit the long-distance, inter-urban motorway: fast, with a smooth alignment cutting across countryside and through woods, with widely-spaced junctions and mostly three lanes wide. But its appearance belies the fact that it's really of regional importance, linking up cities and towns around the Solent and filling up daily with commuters.

There's a good case for it to travel further east and west to help relieve the busy south coast trunk route, reaching Bournemouth and Brighton, but the motorway is constricted by the New Forest National Park in the west, whose guardians the Verderers are unwilling to see road building in the forest, and in the east by - er, nothing. The A27 continues from the M27's eastern end as a four-lane motorway-standard road. For no real reason, this remains part of the A27.

One of the reasons that Southampton and Portsmouth are linked by such a good road is that, in the 1970s as this motorway was being built, there were ambitious plans for a major New Town on the south coast between the two cities: Solent City would have been a vast new urban area, requiring good motorway access. The new city was, in the end, never built.

The M27 forms perhaps the most effective terminus of any London radial motorway. The M3 approaches Southampton via Basingstoke and Winchester, but it's stopped from crashing headlong into the city by the M27 which distributes its traffic east and west.

Start

Cadnam

End

Portsmouth

Passes

Southampton, Fareham

Connects to
Length

24 miles

Open Junctions Section
1972 J1-2 Cadnam → Ower
Dec 1975 J2-4 Ower → Chilworth
Mar 1976 J8-9 Windover → Park Gate
Mar 1976 J9-12 Park Gate → Portbridge
Feb 1978 J7-8 Hedge End → Windover
1983 J4-7 Chilworth → Hedge End

Exit list

Symbols and conventions are explained in the key to exit lists. You can click any junction to see its full details.

Junction   Westbound               Eastbound  
1
0.0 km
Lyndhurst
A337
Bournemouth
Ringwood
A31



A337
WEST
A31



B3078
N/A
LanesLanesLanesLanesLanes Signs LanesLanesLanesLanes Signs
3 miles, 3 lanes 3 miles, 3 lanes
2
7 km
Salisbury
Bath
A36
A326 A36 Romsey
(A3090)
Salisbury
A36
LanesLanesLanesLanesLanes LanesLanesLanesLanesLanes
2 miles, 3 lanes 2 miles, 3 lanes
3
10.7 km
Southampton Vehicle Ferry
Totton
Romsey
M271 Link
M271 M271 Southampton Vehicle Ferry
Totton
Rownhams
M271 Link
LanesLanesLanesLanesLanesLanes LanesLanesLanesLanesLanesLanes
2 miles, 4 lanes 2 miles, 4 lanes
13 km Services Rownhams Services Rownhams
LanesLanesLanesLanesLanesLanes LanesLanesLanesLanesLanesLanes
1 mile, 4 lanes 1 mile, 4 lanes
4
15.2 km
M3 Winchester
Eastleigh
London
M3 Link
LanesLanesLanesLanesLanesLanes LanesLanesLanesLanesLanesLanes
1 mile, 2 lanes 1 mile, 2 lanes
4
17.3 km
Winchester
London
M3 Link
M3
LanesLanesLanesLanesLanesLanes Signs LanesLanesLanesLanesLanesLanes Signs
1 mile, 4 lanes 1 mile, 4 lanes
5
19 km
Eastleigh
Swaythling
Southampton Airport
A335
A335 A335 Swaythling
Southampton Airport
A335
LanesLanesLanesLanesLanesLanes Signs LanesLanesLanesLanesLanesLanes Signs
4 miles, 4 lanes 4 miles, 4 lanes
7
25 km
Thornhill
Hedge End
A334 (A27)
A334
(A27)
A334 Thornhill
Hedge End
A334 (A27)
LanesLanesLanesLanesLanesLanes Signs LanesLanesLanesLanesLanesLanes Signs
1 mile, 4 lanes 1 mile, 4 lanes
8
27.3 km
Sholing
Woolston
A27 (A3205)
(A27)
(A3205)
Sholing
Woolston
A27 (A3205)
LanesLanesLanesLanesLanesLanes Signs LanesLanesLanesLanesLanesLanes Signs
3 miles, 4 lanes  
River or canal River Hamble River or canal River Hamble
  3 miles, 4 lanes
9
32.5 km
Fareham (W)
Whiteley
A27
(A27) Fareham (W)
Whiteley
A27
LanesLanesLanesLanesLanesLanes Signs LanesLanesLanesLanesLanesLanes Signs
3 miles, 4 lanes  
10
37.3 km
Alton
A32
A32 A32
LanesLanesLanesLanesLanesLanes Signs
1 mile, 4 lanes 4 miles, 4 lanes
11
39.5 km
Fareham (Cen)
A27
Gosport
(A32)
(A27)
(A32)
Fareham (Cen)
A27
Gosport
(A32)
LanesLanesLanesLanesLanesLanes Signs LanesLanesLanesLanesLanesLanes Signs
3 miles, 3 lanes 1.5 miles, 4 lanes
41.8 km
LanesLanesLanesLanesLanesLanes
  1.5 miles, 3 lanes
12
45 km


M275
(A27)



Hilsea
Cosham
A27
Portsmouth
Continental Ferry Vehicle Ferry
M275 Link
LanesLanesLanesLanesLanes LanesLanesLanesLanesLanes
1 mile, 2 lanes 1 mile, 2 lanes
12
46 km
Portsmouth
Continental Ferry Vehicle Ferry
M275 Link
Cosham
Hilsea
A3
M275


A3





A27
EAST
A27

A3


LanesLanesLanesLanesLanes Signs LanesLanesLanesLanesLanes Signs
Routes
M27

Picture credits

  • Photograph of M27 at the interchange with the M3 is by Jim Champion.

With thanks to Robert Bollen, Nigel Le Poidevin, Steve, Dave McGuire, Clive and James Denson for information on this page.

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About this page

Published22 April 2017

Last updated12 June 2020