The plan to extend the Joondalup rail line to Butler is a step closer after State Parliament passed the Butler to Brighton Railway Bill 2010.
The $241 million project will extend the rail network from Clarkson 7.5 kilometres north to a new station called Butler.
Transport Minister Simon O'Brien said it was a strategic move.
"With the local population in Perth's north-west suburbs expected to quadruple by 2031, the Butler extension provides a valuable service to these rapidly-growing communities," Mr O'Brien said.
"The project will also ease pressure on the Mitchell Freeway and major road corridors with more than 2,000 passengers expected to board at Butler Station every day," he said.
Butler Station will provide approximately 1,000 car bays, and the project will include the addition of 11 new buses to provide feeder services into Butler and Clarkson stations.
It's expected to be operational by 2014.
The legislation must be proclaimed to establish the legislative authority to go ahead with the planned extension.