Postal ballot forms will start going out on Monday morning for the election to the Ngā Tāngata Tiaki o Whanganui trust.
There are 12 people nominated for four empty seats on the trust, the governance organisation handling the proceeds from the Whanganui River Treaty settlement.
Ngā Tāngata Tiaki was set up with a first intake of seven trustees, and a postal vote will decide who fills those seats from September.
Three of the replacements have already been chosen by the whole-of-river Te Runanga o Te Awa Tupua. They are Alaina Teki-Clark, current deputy chairman Rawiri Tinirau and Joey Allen, who will represent Taumarunui.
That leaves four places, and there are 12 nominees.