New Zealand's TVNZ-One News reported the quake knocked out power to about 5,600 residents, severed water and telephone lines and sent people rushing out of buildings in the towns of Tararua, Manawatu and Taranaki, north of Wellington.
The earthquake was reported about 4 p.m. at a depth of 17.4 miles, with the epicenter 21 miles south-southeast of Palmerston and 69 miles northeast of New Zealand's capital Wellington.
The quake was followed by dozens of aftershocks with magnitudes between 3 and 4.5.
Early reports indicated damage was minor.
Utility officials said they expected to restore power in the affected areas by Monday night.
"We have already restored supply to the majority of customers in Tararua and Manawatu and expect to make steady progress this evening," one official was quoted as saying.
No major fires were reported.
In some places, groceries fell off supermarket shelves and cracks opened up in the driveways of some homes, officials said.
"Pantry contents everywhere," one homeowner messaged on Twitter.
The quake knocked a large eagle sculpture from the ceiling of a building at the Wellington Airport. Television footage showed the sculpture resting on chairs and tables at the food court.
New Zealand is an earthquake-prone region. A 6.3-magnitude quake in 2011 in Christchurch on the South Island killed 185 people and caused extensive damage.