Voting booths across Australia have now closed.
Western Australia was the final state to finish polling at 6pm local time (2000 AEST).
Counting has been under way across the eastern states for two hours, with the result so far extremely tight.
According to the Australian Electoral Commission, there's been a swing of around three per cent against the coalition.
At 8pm (AEST), the coalition government and Labor opposition had secured 55 seats each.
At least 76 seats are needed to form a majority government.
Labor has claimed seats such as Barton in Sydney, and the bellwether seat of Eden-Monaro in southern NSW.
The Nick Xenophon Team's Rebekah Sharkie looks like ousting former minister Jamie Briggs from the blue-ribbon Liberal seat of Mayo in Adelaide.
Labor frontbencher Anthony Albanese says the party is doing well in Tasmania, particularly in Bass and Lyons.
"I think I'd rather be us than them."
Earlier, former Labor leader Kim Beazley said he didn't expect West Australians to be a happy hunting ground for Labor, which holds only three of the 15 lower house seats.
"Western Australians differentiate heavily between federal and state governments ... they certainly know the difference between Turnbull and Barnett," he said.
