Emergency serves were called to the crash, which closed the motorway for several hours, about 9.30am.
Acting Senior Sergeant Anthony Bond said the person who died was the only occupant in the vehicle.
Acting Snr Sgt Bond earlier said there would be delays heading north while an investigation was under way.
The road was initially closed, then by just after midday had reopened to heavy traffic, with diversions in place for other vehicles.
The NZ Transport Agency advised about 3.10pm that the road had fully reopened but delays could still be expected as congestion cleared.
An Otago Daily Times photographer at the scene earlier said the road was closed in both directions.
The vehicle that left the road was completely off the road and could not be seen from the photographer’s vantage point.
