Surviving (and maybe avoiding) an ATO audit

Rudd Mantell Accountants • February 10, 2026

This piece is aimed at self-employed clients, so if you’re a salary earner or a retiree you can safely move on to the next item.

For others, it goes without saying that at tax time you should disclose all your assessable income and only claim legitimate business deductions. Failure to do so exposes you to the risk of penalties and interest on top of the underpaid tax.


And the chances of popping up on the ATO’s radar are not negligible. It runs an active small business compliance program that uses industry benchmarks and other information, including “dob ins” received from community members.


Cash jobs


Offering a discount for cash for a lower price might seem tempting, but it suggests an intention of under reporting income. Tradies and the like occasionally fall out with their clients, some of whom might then report them to the ATO and those “dob ins” can lead to audits being conducted. The practice remains widespread, but you should avoid doing cash jobs – there’s a good chance they will come back to bite you.


Benchmarks


The ATO keeps extensive data of industry benchmarks for many industries, tracking gross income, expenses and profits margins. Its website suggests this data enables you to see how you compare with your peers and perhaps identifies areas for improvement. But it also gives the ATO a way of identifying potential audit cases.


If your trading results are well below the industry average, you might want to think about what some of the reasons for that might be. These could include:


  • Ill health suffered by yourself or a close family member
  • A long holiday
  • Your café or retail business is not in the best location
  • Competition from similar businesses operating nearby
  • You’re inexperienced or just not a great business person.


Averages are just that, and some businesses will be under while others are over. Having an idea of where you sit on the spectrum and why may help you engage with the ATO if and when the time comes.


Lifestyle factors


Another way of identifying cases suitable for audit is for the ATO to assess whether your apparent lifestyle matches the net income disclosed in your tax returns. If you drive a flash car, take expensive holidays, have your children in private schools, have had major home renovations done or get around wearing a Rolex while your disclosed income doesn’t support such a level of spending, you might have some explaining to do.


The audit


If, for whatever reason, the ATO isn’t satisfied that the taxable incomes you have disclosed are correct, they can make their own estimate using whatever information is available. Any amended default assessments will generally be based on a bank account analysis, as well as estimates of private spending. They can’t just pluck a figure out of the air, but they don’t have to prove where the discrepancy came from either.


Those without complete and accurate records of both their business and private finances are vulnerable to adjustments that involve double counting, especially from a bank analysis that assumes that every unexplained deposit represents undisclosed income and every unexplained withdrawal was used to fund private expenditure. As often as not the two are offsetting but the taxpayer can’t prove it.


To challenge a default assessment a taxpayer has to show not only that the ATO’s estimate is wrong in some respect - they also have to show what their correct taxable income is. The courts and tribunals are littered with default assessment cases where the taxpayer has failed in this regard, leaving them with a very large tax bill.


Protective measures


Here are some of the practices that might assist you in an ATO audit. Most of them would need to be in place before an audit even starts:


  • Keep your private and business accounts separate
  • Avoid using cash for business transactions
  • Never run private expenditure through your company account
  • Keep documentary evidence of gifts, loans and other non-taxable receipts that flow through your bank accounts. Create a written record of such transactions as they occur
  • Be prepared to explain any apparent discrepancies between your lifestyle and the income disclosed in your tax returns
  • If you have made a mistake or two, consider making a voluntary disclosure when you are notified of the audit but before it starts. This could help reduce penalties
  • Ensure you have books of account and bank records that verify the taxable income disclosed in your tax returns.


Come and see us to help get you ready for an ATO audit (or avoid one altogether).

By Rudd Mantell Accountants May 5, 2026
From 1 July 2026, employers must pay their employees’ superannuation guarantee (SG) contributions at the same time as salary or wages. This new system is known as payday super.
By Rudd Mantell Accountants May 5, 2026
There is a lot of talk in the media about whether the government is going to change the 50% CGT discount – which currently provides for a taxpayer to be only assessed on half their capital gain.
By Rudd Mantell Accountants May 5, 2026
The Australian Taxation Office (ATO) has issued a warning after spotting a rise in people trying to access their superannuation early, and not always for the right reasons.
By Rudd Mantell Accountants May 5, 2026
In contrast to holiday homes, what happens where you use all or part of your home to produce assessable income?
By Rudd Mantell Accountants May 5, 2026
For many older Australians, having wealth tied up in the family home can make day-to-day expenses challenging. The Home Equity Access Scheme (HEAS) is a government-backed program that allows eligible seniors to unlock some of the value in their home without selling it.
By Rudd Mantell Accountants February 10, 2026
Learn how topping up your super could help reduce your tax bill after a capital gain, and when catch-up concessional contributions may be worth considering.
By Rudd Mantell Accountants February 10, 2026
Explore what debt forgiveness can mean for tax, including key differences between private debts, commercial debts, and possible CGT outcomes.
By Rudd Mantell Accountant February 10, 2026
Read more about permanent incapacity and super, including when total and permanent disability may create an opportunity to access super before retirement.
By Rudd Mantell Accountants February 10, 2026
Learn what can happen for CGT when you buy a new home before selling your old one, and why timing can affect your main residence exemption.
By Rudd Mantell Accountants February 10, 2026
Find out what six key super changes in 2026 could mean for you, from payday super and higher caps to legacy pension flexibility and fund transparency.