Maori names for the North and South Islands are being considered by the Geographic Board.
If changes go ahead, there could be alternative naming - which means means either English or Maori names could be used individually or together.
The Board says 'North Island' and 'South Island' are actually not official names in law, despite their common long-term usage.
It's writing to iwi throughout the country seeking their known traditional Maori names for both islands.
The issue is expected to be put to public consultation next year.
The Maori names, Te Ika a Maui, for the North Island and Te Wai Pounamu for the South Island appear on early official maps and documents.
The Board's research has also shown that Maori names for the islands appear on the very earliest maps and charts, including those of Captain Cook. Cook's chart did not include English names for these islands.