The shake occurred just before midnight last night and was reported by more than 26-and-a-half thousand people from Christchurch to Auckland.
It was the second quake recorded off the West Coast of the North Island last night.
Just a few hours earlier a magnitude 4.7 jolt was felt by more than 3700 people.
The previous record holder was the powerful 2016 Kaikoura earthquake, which received just over 15-and-a-half thousand felt reports.
