The tax office has reminded Australians not to miss the October 31 tax return deadline, or risk being slapped with penalty interest.

“My best advice is to do it now. Don’t wait until next month to sort out your tax return, because then you’ll be too late,” ATO assistant commissioner Graham Whyte told The New Daily.

The last day of October is the last day for Australians to either lodge their own returns, or notify their accountant that they intend to lodge.

October 31 is the last day to lodge or contact your accountant without fear of penalty. Photo: AAP

Thousands of Australians are rushing to meet the deadline. Almost 70,000 returns were lodged on Monday alone.

Many tardy lodgers think they are buying themselves time to pay off an expected tax debt. But not so, Mr Whyte said.

“There’s no reason to put off lodging. Typically, people that put off lodging their return are concerned about having a debt, but your debt will generally be due on November 21 no matter when you lodge.”

If you lodge after the deadline and incur a debt, the tax office will charge you interest on the amount from the day it was due until it is paid, he said.

“This interest charge aims to compensate the community for the impact of late payments, to ensure taxpayers who underpay their tax for a period don’t receive an advantage over those who have paid their tax on time.”

For those expecting a refund, they don’t need to fear a penalty. The ATO is perfectly happy to hold onto your money.

But given that the average return this year has been $2403, surely it’s tempting?

“Most people end up with a refund and it’s your money, so it’s better off in your pocket.”

The Assistant Commissioner also warned Australians that the tax office is cracking down on illegitimate work-related expenses. So don’t claim more than you are entitled to.

For those who are time poor, with uncomplicated returns, online lodgement could be the easiest option. According to the ATO, it is growing in popularity – and is getting even easier to use.

“More than 50 per cent of people are completing their return in less than half an hour using myTax,” Mr Whyte said.

“It is automatically prefilled with information we received from third parties, such as your employer, bank and other government agencies, so all you need to do is add in your deductions, check the information and hit submit.”

Click here for more information on lodging your tax return.