It was opened in stages between 1975 and 1983, providing the largest two urban areas in Hampshire (Southampton and Portsmouth) with a direct motorway link.

Running approximately parallel both to the coast of the Solent and to the A27, the M27 starts as an eastwards continuation of the A31 from Bournemouth and Poole, at Cadnam in the New Forest.

It then runs alongside the northern outskirts of Fareham, briefly with a fourth climbing lane in either direction, before its junction with the M275 to Portsmouth.

The South Stoneham garden of remembrance is now located at the north end of the cemetery, adjacent to the motorway.

[citation needed] Junction 6 was never built – there were plans for a motorway spur (probably to be numbered M273) connecting the M27 to the centre of the Townhill Park area of Southampton.

[citation needed] In November 2015, an elderly woman died after falling from the A3057 bridge that crosses over the M27, into westbound traffic, just before junction 3.

She had not taken her anti-psychotic medication, and escaped from her Southampton home through an upstairs window before climbing off the garage roof and running away.

The commissioning phase began in mid February 2022, during which time the smart motorway technology will be tested, including stopped vehicle detection radars.