The mostly rural area is sparsely populated.
Pohonui-Porewa had the following boundaries with other statistical areas: Moawhango to the north, Whanawhana (towards Hastings, Hawke’s Bay) to the northeast, Tikokino (Central Hawke’s Bay) to the east, Pohangina (Manawatu) to the southeast, Kiwitea (Manawatu) to the south, Tokorangi-Hiwinui (Manawatu) and Lake Alice to the southwest and Fordell-Kakatahi (Whanganui) to the west.
Porewa was one of the first communities in the Rangitikei District to get a school.
A railway station was established in 1887.
By 1897, the rural settlement consisted of a small wooden schoolhouse, two homes, and a one-acre school playground. The school could accommodate 40 students, had a roll of 36, had average attendance of 27, and had a single sole teacher in charge.
The Porewa railway station closed in 1982, and there is now a single track through the site.
In the 2013 census, the Pohonui-Porewa statistical area had a population of 2,031 inhabitants.
In the 2018 census the statistical area was largely divided between Mokai-Patea and Otairi.