The M25 motorway south of Heathrow reopened in both directions ahead of schedule before the Monday morning rush hour.
Work to demolish a bridge was due to close the five-mile stretch between junction 10 and 11 in Surrey between 9pm on Friday and 6am this morning.
However, National Highways said: “On an eerily quiet M25 we finished our work seven hours ahead of schedule and were able to reopen the motorway at 10pm tonight (Sunday 17 March).
“We know many people changed plans and amended their journeys and we’d like to thank everyone who had to make different arrangements due to our work.
“We will announce the date of our next closure as soon as we can.
“We’d like to thank everyone for their co-operation during this closure.”
It had warned that people travelling to Gatwick and Heathrow airports and Channel ports may be affected due to the first time a section of the M25 has been closed for a full weekend.
Both Heathrow and British Airways had urged passengers to build in extra time to reach the airport over the weekend due to the motorway closure.
National Highways said this was the first of five closures between now and September and the date of the next would be announced “very soon to give people as much notice as possible”.
The works are part of a £317 million upgrade to the motorway.
The carriageway between junctions 9 and 11 carries between 4,000 and 6,000 vehicles per hour in each direction between 10am and 9pm on a weekend, according to National Highways.