Cash businesses are a top ATO audit priority. Here is how the ATO uses data-matching, benchmarks, and indirect methods to identify cash economy non-compliance.
The cash economy, businesses that deal predominantly in cash and may not accurately report all income to the ATO, has been a priority compliance target for the ATO for many years. Despite the shift toward electronic payments in the broader economy, the ATO remains highly focused on this area, particularly in the hospitality, construction, and personal services sectors.
If you run a cash-intensive business, understanding how the ATO identifies potential non-compliance, and what happens when it does, is essential knowledge.
One of the ATO’s primary tools for identifying potential cash economy non-compliance is its small business benchmarks, statistical data derived from the tax returns of businesses across a wide range of industries. The benchmarks express key financial ratios as ranges: for example, the ratio of total expenses to total sales, or the gross profit margin, for a given type of business.
If your business’s financial results fall outside the ATO’s benchmark range for your industry, your return is flagged as potentially anomalous. This does not automatically trigger an audit, but it increases your risk profile and may lead to further scrutiny.
Common benchmark ratios include the cost of goods sold to sales ratio, the labour to sales ratio, and the rent to sales ratio. A café that reports a gross profit margin well below the benchmark for cafés in its location and size category will attract ATO attention.
The ATO collects an extensive range of third-party data that it matches against income declared by businesses and individuals. Relevant sources include EFTPOS and credit card transaction data from banks and payment processors; property rental income data from state revenue offices; contractor payment data through the taxable payments reporting system; motor vehicle and property purchase records from state registries; and, under the Sharing Economy Reporting Regime, income data reported directly by digital platforms, covering ride-sourcing and short-term accommodation from 1 July 2023, and food delivery, tasking and most other platform services from 1 July 2024.
If the ATO’s data-matching reveals that your business received substantially more through electronic payments than the income declared in your tax return, or that you have made lifestyle expenditures inconsistent with your declared income, this will trigger further inquiry.
The ATO also receives information from anonymous tip-offs, including from former employees, competitors, and others, which can trigger a targeted audit of specific businesses. The scale is significant: the ATO has received more than 300,000 tip-offs since July 2019 and continues to receive close to 1,000 every week.
In a cash economy audit, the ATO often uses what is known as an indirect method to reconstruct business income where direct evidence of cash sales is limited. The most common indirect method is the goods-based markup approach.
Under this method, the ATO takes the cost of goods purchased by the business and applies a markup ratio consistent with industry norms to estimate the sales revenue that should have been generated. If this estimated revenue is significantly higher than the revenue declared, the difference is treated as undeclared income.
In one case handled by our office, a Sydney company operating six cafés was assessed with a $900,000 tax bill using the indirect method. The ATO’s markup assumptions were based on generic industry data that did not accurately reflect the company’s actual cost structure. Our office successfully challenged the ATO’s methodology and achieved a settlement of $135,000, a reduction of more than 85%.
Another tool in the ATO’s armoury for cash economy investigations is the comparison of a taxpayer’s declared income with their apparent lifestyle. This approach asks whether the taxpayer’s consumption, assets, and expenditure are consistent with their declared income.
The ATO uses data from various sources to build a picture of a taxpayer’s lifestyle: property ownership, vehicle registrations, overseas travel records, and bank account data. A business owner who declares a modest income but owns multiple investment properties, takes regular overseas holidays, and drives a luxury vehicle may attract scrutiny.
This approach is particularly effective in cases where a business owner has extracted cash from the business without declaring it as income.
The best protection against a cash economy audit is a well-maintained set of financial records that accurately captures all income and expenditure. This means using a recognised accounting system, maintaining point-of-sale records, retaining all receipts and invoices, and reconciling daily cash receipts against sales records.
If your business has historically not maintained records to this standard, or if you are aware that income has not been fully reported, addressing this proactively through a voluntary disclosure and improved record-keeping is strongly advisable. The ATO now badges this work as its ‘shadow economy’ program, the dedicated Shadow Economy Compliance Program has been extended through to 30 June 2028, and its detection capabilities continue to improve.
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