In Australia, Working Holiday Makers working for Employers that are registered for the WHM program are taxed on a year-to-date earnings basis, rather than a pay-to-pay basis.
Therefore, the standard tax scales do not apply and instead you need to set the employee’s Tax Scale to Fixed Tax Rate and the rate appropriate to their year-to-date earnings.
Most Working Holiday Makers will not earn more than the initial tier (2024/25: $45,000) and be taxed at the lowest rate (2024/25: 15%). If an employee’s year-to-date earnings do exceed the initial tier then the Fixed Tax Rate will need to be adjusted.
The rates can be found here:
https://www.ato.gov.au/tax-rates-and-codes/schedule-15-tax-table-for-working-holiday-makers
In the rare event a Working Holiday Maker earns more than the tier 1 amount and they continue employment into a new financial year, their Fixed Tax Rate should be reset to the minimum value.