In some situations, tax amounts in software packages such as Lightning Payroll may differ slightly to the PDF tax tables or XLSX lookup tools that the ATO provides.
If you find your tax is differing slightly in the software please test the tax amounts using the ATO's own app. You will find that the tax amounts in their app matches our software.
We have confirmed with the ATO that this is normal. In their words, through private correspondence:"Payroll or accounting software written in accordance with the formulas in this schedule should be tested for accuracy against the sample data.
The results obtained when using the coefficients in this schedule may differ slightly from the sums of the amounts shown in the PAYG tax tables. The differences result from the rounding of components. Withholding calculated using either method is accepted."