Two deaths have been confirmed - one in Kaikoura and one in Mt Lyford, east of Hanmer Springs.
The tsunami warning has now been downgraded to a marine and beach threat, which remains in place from Napier to north of Dunedin and Chathams Island - find your local evacuation zone here and your local Civil Defence group here.
Tsunami waves were recorded in and around Kaikoura and parts of Wellington.
All trains in the South Island and all trains on the North Island main trunk line south of Palmerston North are cancelled until further notice.
The Education Ministry is advising schools from North Canterbury to Wellington not to open until the buildings can be checked.
All airports are open.
The full extent of the damage to transport systems is still unfolding with extensive damage caused to parts of State Highway One in the South Island.
The severe 7.5-magnitude quake struck near Hanmer Springs just after midnight.
Dozens of aftershocks have struck up and down the country, as far north as Pukekohe, south of Auckland.
Go to Newshub for live updates