Civil defence authorities asked people in the Tologa Bay area to leave their homes after a 7.1 quake struck 169km (105 miles) north-east of Gisborne.
People in some coastal areas were told to go to higher ground.
The quake caused a tsunami but it has had no noticeable impact, an emergency worker told New Zealand radio.
The Pacific Tsunami Warning Center in Hawaii tweeted that only a 21cm (8in) wave had been measured.
The quake occurred at 04:37 local time (16:37 GMT) at a depth of 19.1 miles, US monitors say.
Residents across North Island said they felt shaking and rattling as the quake struck but there were no immediate reports of serious damage.
In 2011, the city of Christchurch on South Island was devastated by a magnitude 6.3 earthquake that left 185 people dead.
Each year more than 15,000 earthquakes are recorded in New Zealand, but only about 150 are large enough to be felt.