Senior figures on both sides of politics have said they have doubts about the length of the period available to vote early - this year, it's as long as three weeks.

Treasurer Josh Frydenberg said the early-voting period made it hard for MPs holding portfolio responsibilities to cover their electorates as well as other parts of the country.

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"It does feel a bit long, three weeks," he told reporters this week. "That's an issue that will probably be revisited by both sides of politics after this election."

Labor frontbencher Anthony Albanese said the length of pre-poll voting should be reviewed because while it was "very valuable ... three weeks is a very, very long time."

In the New England electorate, about 7 per cent of the electorate have already visited one of the region's pre-polling booths.

That number is expected to rise rapidly to more than 30 per cent by election day on May 18.

In 2007, pre-poll votes, excluding postal votes, were at 8.2 per cent, rising to 22.7 per cent in 2016.