Minister for Transport and Infrastructure Andrew Constance has announced peak services would be doubled on the South West Rail Link by the end of the year, and customers would have direct access to more destinations across Sydney.

The $2.1 billion South West Rail Link opened in February this year, ahead of schedule and $300 million under budget.

Mr Constance said the rail line was proving popular with locals in Sydney's fastest growing region, with more than 1,500 train journeys every weekday from new stations at Leppington and Edmondson Park.

"On Sunday December 13 we will connect the rail line with the rest of the train network and services will become part of the T2 South Line travelling via Liverpool and Granville meaning more services and more options for customers.

"Peak hour frequency from the South West will double, from a train every 30 minutes to one every 15 minutes – a great outcome for locals.

“For the first time customers will be able to get a direct service to the city and improved access to key employment hubs including Parramatta and Liverpool. Travel data tells us this is where our customers are choosing to travel.

“Some customers travelling to the Sydney CBD may still find it faster to interchange at Glenfield to travel via the airport, and for them more services means less time waiting to change trains.”

The NSW Government explored integrating the South West Rail Link via the Airport Line, however adding extra trains would have slowed down services, not only for South West customers, but for customers who travel from Campbelltown and Macarthur each day.

The new timetable for the South West Rail Link is still being finalised, but it is anticipated the peak 15 minute frequency will remain in place for most of the day. Some low-demand services in the off-peak will continue to run every 30 minutes to Glenfield and Liverpool.

“The South West is expected to house 300,000 new residents in the next decade. As the population grows the Government will continue to monitor patronage to determine the best service patterns,” Mr Constance said.