Whanganui District Health Board members yesterday voted 9-2 to add the "H" into the hospital's name, and the change is expected to be completed by the end of next year.
Members Ray Stevens and Allan Anderson voted against it.
Mr Anderson referred to the boarddecision in June 2013 to spell the hospital name with an "H" when speaking Maori, but to spell it without when speaking English, which board member Michael Laws called an "elegant solution".
Mr Anderson said the decision was made out of "mutual respect".
"I went to see mutual respect, I want to see dignity maintained by both parties," he said.
Health board chief executive Julie Patterson said the decision had already been made by Minister for Land Information Maurice Williamson who indicated he expected Crown agencies to move towards using Whanganui over Wanganui.
Kate Joblin said the board needed to "get on with it" and put in the "H".