The NZR S class was a class of seven 0-6-4T single Fairlie steam locomotives used in New Zealand.The locomotives were ordered by the New Zealand Railways Department (NZR) in 1880, and delivered from the Avonside engine works in 1881–1882. They were considerably larger than the earlier R class, and all saw service in the Wanganui district, with its abundance of sharp curves and grades.