Road closures, diversions and major congestion caused by an overturned HGV on Wednesday afternoon (October 12) have all cleared following overnight repair work.
The M4 was closed westbound between junction eight and junction 10 overnight but was reopened at around 6am on Thursday.
The HGV flipped shortly before 1pm, causing a diesel spillage and garden waste to be strewn across the carriageway.
Highways England carried out resurfacing work as well as repairs to the central reservation, which was damaged in the crash.
The driver of the lorry was taken to hospital for treatment, suffering from "serious injuries" according to police.
Reopened by Highways Agency
A statement from Thames Valley Police said: “The westbound carriageway of the M4 at J8/9-10 was reopened overnight by the Highways Agency.
“The road was closed following a collision on the westbound carriageway at about 12.45pm yesterday.
“A truck overturned and the driver has been taken to hospital with serious injuries.
“Thank you for your patience and co-operation while we carried out work at the scene along with partner agencies.”