Annual Leave: What to Check Before You Trust the Number

Updated 27 June 2026 · Tax and pay

A Annual Leave Calculator gives a fast answer, but the answer is only as good as what goes in. These are the mistakes we see most often with annual leave calculations in Australia, and how to avoid them.

1. Forgetting the Medicare levy

Most take-home pay estimates that leave out the 2% levy overstate pay by hundreds or thousands of dollars.

2. Using last year’s tax rates

Brackets and offsets change. The Stage 3 changes from 1 July 2024 and further cuts from 1 July 2026 mean older figures can be well off.

3. Treating a deduction as a refund

A $1,000 deduction reduces taxable income by $1,000. The cash benefit is only your marginal rate on that amount.

4. Confusing marginal and average tax rates

Moving into a higher bracket only raises the tax on the dollars above that threshold. Your average rate is always lower than your marginal rate.

5. Overlooking the detail that matters most here

Shift workers under some awards get 5 weeks a year. Casuals do not accrue paid annual leave.

How the annual leave accrued changes with weeks worked

A common mistake is getting one input slightly wrong. Here is what happens to the annual leave accrued when “Weeks worked” is off by up to 20% in either direction, with everything else held steady.

Weeks worked	Annual leave accrued
42	122.8 hours
47	137.4 hours
52	152 hours
57	166.6 hours
62	181.2 hours

At 42 the result is 122.8 hours; at 62 it is 181.2 hours. If a small change in this input moves the answer a lot, it is worth double-checking that figure before you rely on the result.

A quick sense check

Full-time and part-time employees accrue 4 weeks per year of ordinary hours: hours per week × 4 × weeks worked ÷ 52. With typical inputs the calculator returns annual leave accrued of 152 hours. If your own result looks wildly different, check that each figure is in the right unit and period (weekly, monthly or yearly) before drawing conclusions.