How tax refunds actually work in Australia
A refund isn't a bonus from the government — it's the difference between what your employer withheld through PAYG and what the ATO assesses you owe after you lodge. When too much was withheld, you get the gap back. When too little was withheld (or you have untaxed income), you pay the gap.
The formula in one line
Refund = tax withheld − (income tax on taxable income + Medicare levy + HECS). Taxable income is your gross income minus allowable deductions. The income tax piece uses the FY 2025-26 resident scale: tax-free to $18,200, 16% to $45,000, 30% to $135,000, 37% to $190,000, and 45% above. The 2% Medicare levy lands on top for most taxpayers earning over roughly $27,000.
Worked example
Say you earn $95,000 gross, your employer withheld $22,000 of PAYG, you have $1,500 of work-related deductions, no HECS, and you elect the Medicare levy:
- Taxable income: $95,000 − $1,500 = $93,500
- Income tax: $4,288 + ($93,500 − $45,000) × 30% = $18,838
- Medicare levy: $93,500 × 2% = $1,870
- Total assessed: $20,708
- Refund: $22,000 − $20,708 = $1,292
The five biggest reasons your refund is bigger (or smaller) than expected
- A second job using the tax-free threshold. Both employers withhold as if you earned only that amount — you get hit with the gap at tax time.
- Untaxed side income. Uber, freelancing, dividends without franking, crypto sales — none of it has tax withheld.
- A pay rise mid-year. PAYG smooths over the full year; if you got a bump in March, withholding catches up only after assessment.
- HECS withholding lag. Bonuses and commissions push you over a HECS threshold your regular salary doesn't.
- Missed deductions. Home office hours, professional memberships, ATO myDeductions — small claims add up to hundreds back.
When you'll see the money
Lodge through myGov and most refunds land in your bank account within 5–10 business days. The ATO publishes batch processing dates each year — if yours is delayed past two weeks, check that your bank details and prior-year returns are up to date. Paper lodgement takes 6–10 weeks.
What this calculator does not model
The Low Income Tax Offset (LITO, up to $700 below $66,667), Seniors and Pensioners Tax Offset (SAPTO), Medicare Levy Surcharge, private health rebate, franking credit refunds, foreign income, capital gains, and trust distributions are all out of scope. For a precise figure, use the ATO's official Income Tax Estimator or speak to a registered tax agent.