Polling booths have now opened in Western Australia, joining those in the eastern states that flung open their doors two hours earlier, with millions of voters set to choose the next federal government.

More than 16 million Australians are set to take part in the national vote, with a record enrolment rate of 96.8 per cent.

They have until 6pm on Saturday to cast their votes at 7000 polling locations across the country.

About 4.76 million votes have been cast at early-voting centres, with 700,000 votes cast on Friday, the final day of campaigning.

This compares to a total of 2.5 million at the same stage of the 2016 federal election.

In addition, there have been 1.5 million postal vote applications, the AEC said.

More than 1500 candidates have thrown their hat into the ring across 151 electorates, including more than 400 candidates contesting 40 Senate vacancies and just over 1000 people vying for 151 House of Representatives seats.

The final Newspoll of the campaign had Labor ahead of the coalition 51.5 to 48.5 on a two-party preferred basis while the last Ipsos poll had Labor ahead 51-49.

-AAP