A technical glitch has left 10,000 Telecom customers without a broadband connection.
Parts of Wellington, the east of the North Island and areas of the South Island have been affected by the fault.
A Telecom spokeswoman said attempts by technicians to fix the problem overnight have been unsuccessful.
She said the company is considering offering compensation for customers affected by the outage for more than 24 hours.
The problem was earlier blamed on a "remote access node" or "RAN".
Dial-up, mobile broadband and landline services were not affected and broadband for all other customers was running as usual, Telecom said.
- NEWSTALK ZB, NZPA