The quake at 8.24am local time (6.24am AEDT) had a depth of 9km and was centred 10km south of Seddon.
GeoNet recorded the shaking as strong, and it was reported by over 1200 people in the immediate minutes afterwards.
The earthquake was felt as south as Rakaia, and as north as Palmerston North, on the North Island.
One person who was six floors up from the ground said that it was “a good shake.”