The Class 450 Desiro trains operate on certain London commuter rail routes, as well as outer suburban and regional services from London Waterloo, and local services outside of the London area.
They can also be found on London commuter rail services usually operated by Class 455 units (to Woking, Guildford, Dorking, Chessington South, Hampton Court, Shepperton and the Kingston Loop Line), particularly in the peaks and on Sundays during periods of engineering work.