It happened shortly after 12pm and the eastbound lanes were closed off by police. They remained shut for more than an hour while emergency services and recovery vehicles responded to the incident.
Traffic Wales earlier tweeted warning motorists to “expect delays” after the motorhome overturned and was blocking the road. As well as hitting traffic on the A55 it also saw roads jammed around the area as drivers tried to avoid the expressway.
There were no reported injuries and the road was reopened about an hour later, after the accident site was cleared. But the incident continued to impact traffic as queues were gradually cleared.
A North Wales Police spokesman said: “Shortly after 12.20pm today, we attended a road traffic collision on the A55 Eastbound between Llanddulas and Pensarn. A motorhome has overturned and is blocking the road. The road remains blocked whilst the vehicle awaits recovery.”
The Welsh Ambulance Service was not required.