The Melbourne-based outfit will enter the competition in season 2019-20, with the Sydney side set to join the following year.
FFA chairman Chris Nikou says he hopes the league continues to grow. «Expansion is an ongoing dialogue for us. Obviously a lot of stakeholders to consult. We would like to keep the expansion issue on the agenda».
Western Melbourne and Macarthur are the first to join the league since Western Sydney Wanderers in 2012-13.
Western Melbourne and Macarthur South-West Sydney were chosen from a shortlist of six bids, with Team 11 from Dandenong, former NSL club South Melbourne, Sydney's Southern Expansion and Canberra United missing out.
The six final bids were whittled down from 15 hopefuls.
