The 36km line will open in early 2019 with 13 metro stations, 4,000 commuter car parking spaces and up to 15 trains an hour.
NSW Premier Mike Baird said the project would provide essential public transport for the local community.
“This rail line will transform the lives of people in Sydney’s north-west, enabling commuters to catch a train every four minutes in the peak,” Mr Baird said.
Over 4,600 people from the Western Sydney region worked on the tunnelling project, using four tunnel boring machines to create Australia’s longest railway tunnels.
More information on the project is available on the Sydney Metro fact sheet (PDF 205KB).