The 5.1 magnitude quake hit at a depth of 7km about 5km south of Te Aroha in Waikato at 5.39am.
More than 20,000 people reported feeling a shake in the areas nearby, including Hamilton, Tauranga, Rotorua and Auckland.
It was followed by two 2.7 magnitude tremors in the same spot at 5.47am and 5.51am.
About 8000 people reported feeling the first aftershock, and about 4000 said they felt the second.
Truck driver Darryn Phayer said his 25-tonne truck swayed sharply in the first quake.
"The truck started violently shaking and I thought 'oh what's going on here', but literally, prior to that, in the farm across the road from the yard, a bunch of dogs started barking and I thought 'Oh what's upset them' and within a couple of minutes, it was up on GeoNet.
"[It] scared the living daylights out of me, to be honest."
It comes after a 3.9 magnitude quake happened in the same area last week.
GeoNet said they were likely on the same fault system.
The area last had a strong quake in 1972 with a 4.9 magnitude quake, GeoNet said.
