More than $50 billion in uncollected debt is owed to the tax office as the nation's taxation tsar puts Australian businesses of all sizes on notice.
In his final speech as taxation commissioner, Chris Jordan called out the growing number of profitable businesses choosing not to pay their fair share of tax.
"Businesses are starting to appear to de-prioritise the payment of tax obligations," Mr Jordan told a tax summit at the Melbourne Convention and Exhibition Centre on Wednesday.
"This is concerning and it is out of step with what we know, which is the vast majority of taxpayers pay on time and it is unfair to them that some choose not to.
"We are hearing more and more from tax professionals that some businesses are simply rolling the dice, treating ATO liabilities like a free loan. This is not acceptable."
Small businesses owe more than $33 billion of the $50.2 billion pool of outstanding collectable debt, including $23 billion from unpaid business activity statements.
While acknowledging the fraught economic conditions, Mr Jordan said the tax office was cracking down on deliberate fraud through embedded systems and a new detection unit with 500 dedicated staff.
But he pointed out tax professionals also had a role to play in keeping businesses above board.
"You can reinforce to your clients they are only the temporary custodians of GST, pay-as-you-go withholding and super guarantee - it's not their money," Mr Jordan said.
"You know the signs when a business is struggling, on the brink of insolvency, or perhaps simply needs to be told the time may have come to exit gracefully."
Mr Jordan emphasised a change in mindset is still required from taxpayers and tax professionals alike to facilitate greater take-up of digital services.
More than one in five of the 1.4 million answered calls to the ATO this financial year have been from tax professionals, and many of the requests and queries could have been dealt with online.
"In 2023, we simply can't still be receiving close to one million paper business activity statements and us sending out cheques," Mr Jordan added.
Mr Jordan will step down as taxation commissioner when his second term expires at the end of February next year, after more than 11 years in the top job.