Submitters may be able to suggest names for the northern and southern Māori constituencies.
Horizons councillors decided to add Māori constituencies in May. They held workshops in June and August to decide how to change representation.
On August 24 they had four options to choose between. Two had a total of 14 councillors, with either one or two Māori constituencies.
The other two kept councillor numbers at 12, with one or two Māori constituencies.
Several councillors said they were reluctant to increase the total number of councillors to 14. But keeping it at 12 would mean decreasing Palmerston North representation from four to three councillors, and decreasing Horowhenua representation from two to one councillor.
The Ruapehu and Tararua constituencies are small, giving each slightly more voting power, but they were considered distinct "communities of interest".
About 54 per cent who made submissions on the representation review preferred one Māori constituency to two.
Council deputy chairman Jono Naylor said having just one Māori constituency would pull in the very best two people from across the region. They would represent Māori and not their geographical area, iwi or hapū.
But Emma Clarke said the Whanganui River was now a "legal person" - an idea that deserved representation. Nicola Patrick said the northern end of the region had strong interlinks and Weston Kirton said the council's two Māori representatives could both be from Palmerston North if there was just one Māori constituency.
Cotton said he preferred the council to stay at 12 councillors, and the influence of Māori constituencies would be "watered down" if there were 14 councillors. The councillors representing Māori will have the same obligations and take the same oath as the others, he was told.
Keeping the value of everyone's vote the same would be impossible with just 12 councillors, Fiona Gordon said. And having Ruapehu and Tararua overrepresented was better than forcing councillor numbers down, Patrick said.
The larger number of councillors will share the same amount of money, so the increase will have no impact on ratepayers.
"I'm really happy as a committee chair to adjust down the increased percentage that I get to support spreading the money a bit further," Patrick said.