Australian Taxation Office (ATO) assistant commissioner Karen Foat said when people lodge their tax returns at the last minute, they start to see some "easily avoidable" errors.
The warning comes as the final fortnight of tax time begins with the ATO encouraging people to take advantage of potential refunds by lodging their return or engaging a tax agent by October 31.
Last year, around 475,000 taxpayers who completed their own return lodged late. Of these late lodgers, more than 300,000 had been missing out on refunds as a result.
"We know that tax can seem complicated, which is why we see so many people putting it off. People should know that it's actually becoming increasingly quick and painless to lodge your return," Ms Foat said.
"Your tax return can be done from the comfort of your own living room, just by going online and logging into myTax (accessed via myGov). Some taxpayers have even told us that they've completed it whilst on the bus, it's that easy. For the majority of taxpayers, this takes less than half an hour.
"One common thing we see is people losing track of receipts that have been thrown out by taxpayers thinking they didn't need them anymore.
"People need to remember to keep receipts for all deductions they want to make. We can ask you to substantiate your claims at any time, even up to five years after the return is lodged."
Ms Foat said they often hear some "pretty creative excuses" around tax time.
Here are the ATO's top-five weirdest tax time excuses:
- Someone's stolen my pants: One taxpayer had a thief break into their car and walk off with their uniform pants. Unfortunately, the taxpayer had kept their receipt in his pocket and couldn't provide a record of their purchase.
- I've got 'holiday brain': One reason for late lodgment we've been given is that a taxpayer had gotten 'holiday brain' after returning from a trip and had forgotten to lodge their tax return.
- A mouse ate my receipts: The most common problem that we keep seeing excuses for is missing receipts. One taxpayer contended that a mouse had broken into their car and eaten their receipts.
- The car wash did it: Leaving receipts in cars seems to frequently cause taxpayers strife. We heard from one taxpayer, who, while trying to get their car squeaky clean, vanished all traces of their purchase.
- I've got too many to do: We often hear that taxpayers put off doing their latest return because they have several returns overdue.