All lanes and slip-roads will re-open from tomorrow morning (Friday) from 6am, after Wokingham Borough Council announced it had finished the works ahead of schedule.
The improvement scheme, which aims to replace the bridge's noisy joints and improve drainage and signage, started in July and was due to finish yesterday (.
Cllr Chris Singleton, deputy executive member for planning and highways, said: "First and foremost we would like to thank everyone who uses Loddon Viaduct for bearing with us while this essential work was carried out; for taking alternative routes or allowing more time for their journeys.
“They certainly made a difference, helping to keep traffic problems to a minimum.
“The traffic management designed by our highways team also ensured surrounding roads didn’t take the brunt of the lane closures on the viaduct, and we worked efficiently and solidly throughout to make sure the project stayed on schedule.
“We had always hoped to finish ahead of time because we know how important this route is, and didn’t want to inconvenience road users and local residents for any longer than necessary.”
To minimise traffic disruption, the work carried out his summer focused only on the eastbound carriageway towards Bracknell.
Work on the westbound carriageway towards Reading is due to be carried out during the school summer holidays next year when again roads are seasonally quieter.