The state government will investigate the viability of a nighttime 'black' CAT bus route as part of a wider review of the successful service.

The review will be the first since the Green CAT (central area transit) service was introduced in 2013.

A nighttime CAT is on the cards. Credit:Hamish Hastie

It will include investigating demand for the black CAT service which, subject to funding, could link residential developments, hotels and entertainment areas in east and west Perth with the city centre’s main entertainment districts.

The latest CAT buses currently operate is 8pm on Friday nights.