A127

A127
Click map to enlarge
Major junctions
West end:	London (Romford)
	A12 road M25 motorway Junction 29 A128 road A130 road A1245 road A13 road
East end:	Southend-on-Sea
Location
Primary destinations:	Basildon
Road network
Roads in the United Kingdom Motorways A and B road zones

The A127, also known as the Southend Arterial Road, is a major road in London and Essex, England. It was constructed as a new arterial road project in the 1920s, linking London with Southend-on-Sea, replacing the older A13. Formerly classified as a trunk road, it was "de-trunked" in 1997. It is known as the Southend Arterial Road except for part of its length in Southend-on-Sea. It is also streetlit for its whole length despite its majority coverage through rural land.

The A127 starts as a turning off the A12 at Gallows Corner in the London Borough of Havering. Traffic heading towards London goes over a flyover and joins the A12 traffic which merges onto the slip-road from the roundabout below, which is where the A127 ends. Traffic heading towards Southend also uses the flyover as well as slip roads. Its first significant junction is a crossroads after ¹⁄₂ mile (0.80 km) (Squirrels Heath) with Squirrels Heath Road and Ardleigh Green Road. There are traffic lights here, but after that, there are no traffic lights or roundabouts until it enters Southend-on-Sea, though there are a few side turnings.

Major junctions follow the layout similar to motorways, being served by high-level or low-level roundabouts accessed via slip roads, except for the straight flyover at the junction with Hall Lane, Upminster at about 3.5 km east of Gallows Corner. 4 miles (6.4 km) after Gallows Corner the A127 crosses the M25 motorway at M25 Junction 29 - the start of slip-roads on the A127, and then immediately crosses into Essex. After a couple of minor side road exits, the next major junction is with the A128 Brentwood exit at the Halfway House (pub) near West Horndon, 3 miles (4.8 km) east of the M25.