The boat was off the Kaikoura peninsula, near Point Kean, when the incident happened on Thursday morning.
A Maritime NZ spokeswoman said the group made contact with the Rescue Coordination Centre about 9.30am.
The Coastguard, South Pacific Helicopters and Life Flight were alerted.
All three made it safely to shore, where they were collected by the helicopter.
They were uninjured and the Herald understands they were wearing lifejackets.
Life Flight was stood down and the boat was towed back to shore.
The incident follows a fatal boating incident near Kaiapoi on Wednesday.
Police said inquiries are under way to establish how the person died.
A spokeswoman said police were notified about the incident about 7.30am.
"We can confirm that it's not a drowning incident," she said.
The boat was found on the Waimakariri River around 8am, she said.
