A 5% payroll error sounds small.
On one payslip, it might be.
Across 20 employees, 52 weeks, superannuation, penalty rates and other entitlements, it can become a significant financial and compliance problem.
For Australian employers, payroll is not simply a matter of multiplying hours by an hourly rate. Modern awards can involve classifications, overtime, penalty rates, allowances, casual loadings and other conditions that change depending on when, where and how an employee works.
In 2026, minimum award wages increased by 4.75% from the first full pay period starting on or after 1 July, making current award interpretation and payroll configuration even more important.
Here is what a seemingly small payroll error can really cost.
1. See What 5% Looks Like Over a Full Year
Consider a business with a weekly payroll of $40,000.
If an award interpretation or payroll configuration error causes employees to be underpaid by an average of 5%, the immediate difference is:
- Weekly underpayment: $2,000
- Monthly equivalent: approximately $8,667
- Annual underpayment: $104,000
The original mistake may have been something as simple as applying the wrong classification, missing a penalty rate or incorrectly configuring an allowance.
But once that mistake is repeated automatically every week, the payroll system does exactly what it has been told to do — including repeating the error.
That is what makes systematic payroll mistakes particularly expensive.
2. The Cost May Not Stop at Wages
Now consider superannuation.
From 1 July 2026, the super guarantee is calculated at 12% of qualifying earnings, and Payday Super requires employers to pay super with each payroll cycle, generally with the contribution reaching the employee’s fund within seven business days.
If the entire $104,000 underpayment in our simplified example also represents earnings on which super is payable, the missed super could add another:
$104,000 × 12% = $12,480
That takes the potential wage and super shortfall to:
$116,480
And that is before considering whether the error also affected leave calculations, payroll tax, workers compensation premiums or other employment costs.
The exact consequences depend on what was underpaid and the applicable employment arrangements, but the principle is clear: payroll errors rarely exist in isolation.
3. Award Interpretation Is Often Where Problems Begin
Payroll software can calculate accurately while still producing the wrong result.
Why?
Because software depends on the rules entered into it.
Common areas businesses should review include:
- employee award coverage;
- classification levels;
- ordinary hours;
- overtime triggers;
- weekend and public holiday penalties;
- casual loading;
- allowances;
- annualised wage arrangements; and
- changes to award rates.
Most award-covered employees are entitled not only to the applicable minimum rate but also any penalties and allowances required under their award or agreement.
Employing someone at a salary above the base award rate therefore does not automatically mean every award obligation has been dealt with correctly.
4. One Wrong Setup Can Affect an Entire Team
The biggest risk is often not an isolated data-entry mistake.
It is a system error.
Imagine five employees are assigned to the wrong classification in the payroll system. Every ordinary hour, overtime shift and weekend worked from that point may be calculated using the incorrect settings.
If nobody reviews the underlying configuration, the problem can continue for months or years.
That is why payroll controls should focus on both:
transactions and setup.
Checking whether this week’s payroll total looks reasonable is useful. Checking whether the employment rules producing that total are correct is even more important.
5. Good Payroll Needs More Than Software
Reliable payroll should have several layers of control.
A practical process might include:
- Correct employee setup
Confirm employment type, award, classification and relevant conditions when the employee starts or changes roles. - Current award rates
Update payroll when award rates, allowances or other entitlements change. - Timesheet controls
Make sure hours, overtime, breaks and relevant shift information are captured accurately. - Payroll review
Have someone review unusual movements, overtime, allowances and employee changes before the pay run is finalised. - Periodic payroll audits
Test a sample of employees back to their applicable employment conditions rather than relying solely on software calculations.
Employers must also maintain relevant time and wage records for seven years, making good record keeping an essential part of payroll compliance.
6. Fixing Payroll Later Is Usually More Expensive
When an underpayment is eventually identified, the business may need to review historical payroll, calculate differences employee by employee, correct superannuation and other affected amounts, contact current and former employees and maintain evidence of the remediation process.
There can also be regulatory consequences.
Since 1 January 2025, intentionally underpaying employee wages or entitlements can constitute a criminal offence under Australian workplace law. Honest mistakes are not captured by that criminal offence, but employers still need to rectify genuine underpayments and meet their broader workplace obligations.
The Practical Takeaway
A 5% payroll discrepancy is not a 5% problem when it repeats every pay cycle.
The best payroll system is not simply one that processes wages quickly. It is one where the underlying award rules are configured correctly, changes are monitored, exceptions are reviewed and management has confidence that employees are being paid properly every week.
At The Weft Advisory, we look beyond the final payroll number. We help businesses build stronger payroll processes, reporting and financial controls so small configuration errors are identified before they become large historical liabilities.
