The official spelling of this region's name is changing to Manawatū-Whanganui.
The final decision was made by Land Information Minister Eugenie Sage, following an application to the New Zealand Geographic Board by Horizons Regional Council a year ago. The application was made after consulting iwi.
The change takes place from October 18.
Horizons is the council's trading name. Its official name will be Manawatū-Whanganui Regional Council.
The Whanganui spelling is consistent with the views of local tribes, a statement from the New Zealand Geographic Board said. It also matches the spelling of the Whanganui River, Whanganui National Park, Whanganui District and Whanganui town.