Matangi electric multiple unit trains are operated under the Metlink brand through this station in both directions to Johnsonville (to the north) and Wellington (to the south).

Ngaio was one of three stations constructed by the Wellington and Manawatu Railway Company on what is now known as the Johnsonville Branch.

The points were manually controlled from a signal box at the southern end of the station into the 1960s,[5] with this being one of the last such sections of the line before complete automation.

Runaway sidings are located at both the southern and northern ends of the station for Down and Up trains (respectively).

Trains run in both directions through this station, departing at half-hourly intervals, supplemented by a 13/13/26 schedule at peak times on week days.