The incident happened at around 05:55 BST, resulting in the death of the taxi driver at the scene. The closure affected a 23-mile (37km) section of the A55 eastbound, from junction 11 (Llandegai) to junction 19 (Glan Conwy), as North Wales Police conducted an investigation.
The taxi involved in the crash was confirmed to be a white Hyundai from the Premier Group. The company expressed its condolences to the deceased person's family and stated that it was cooperating with the police investigation.
The road closure forced motorists to take a 39-mile (63km) detour until a single carriageway section of the A55 eastbound at Dwygyfylchi reopened in the afternoon. Both lanes of the A55 finally reopened shortly before 19:00.
The next of kin and the coroner were informed of the death, and the North Wales Fire and Rescue Service sent crews to the scene.