Air New Zealand has apologised for a website Niue on Sale ad page in July that featured an image of palm trees and verdant green islands.
The company said in response to a complaint from a viewer that an employee stand-in had loaded the wrong page.
The viewer called the ad misleading, noting that Niue, known as "the rock" because of the way its cliffs rear out of the sea to a height of 120m, has no islands.
The viewer complained to the Advertising Standards Authority's complaints board.
The airline said sorry for any confusion and that the offending image had been updated.