Tools · Money & tax
Side hustle tax calculator
If you've got a job and a side hustle, your side hustle income doesn't get its own tax-free threshold — it stacks on top of what you already earn, and gets taxed at your marginal rate from the first dollar. This calculator shows you what that actually looks like: how much extra tax you'll owe, and how much to set aside from every payment so tax time isn't a shock.
Key points
- Side income is taxed at your marginal rate — the rate that applies to your highest dollar of combined income, not a separate rate for the side hustle.
- There's no extra tax-free threshold for a second income stream. Your one tax-free threshold is already used by your main job (if you've claimed it there).
- This is an estimate for general information — it doesn't replace advice from a registered tax agent.
How this is calculated
We calculate tax (income tax + Medicare levy, and HELP/HECS repayments if applicable) twice: once on your salary alone, and once on your salary plus side hustle profit. The difference between the two is the genuine cost of the side income — this is more accurate than applying a single "your tax bracket" percentage, because it correctly handles cases where your side income straddles a bracket or repayment threshold.
This is an estimate for general information, based on standard resident tax rates. It doesn't account for deductions, offsets (like the low income tax offset), the Medicare levy surcharge, HELP/HECS indexation, or your specific circumstances.
Why "set aside a percentage" is safer than guessing
When an employer pays you, they withhold tax through PAYG before the money even hits your account — so by the time you lodge a return, most of what you owe is already covered. Side hustle income doesn't work that way. Nothing is withheld, so the full amount lands in your account, and it's easy to spend what actually belongs to the ATO. That's how side hustlers get caught out at tax time.
The set-aside percentage above is rounded up from your actual marginal rate, so it builds in a small safety margin rather than leaving you exactly on the line.
Frequently asked questions
Do I have to pay tax on side hustle income?
Yes — if you're carrying on a business or enterprise, you must declare all of that income whether or not you hold an ABN. See our guide on whether you need an ABN for a side hustle for how the ATO and ABR draw that line.
What if my side hustle makes a loss?
This calculator assumes a profit. If your side hustle makes a loss, different and more complex rules apply (the ATO's non-commercial loss rules determine whether you can offset it against other income) — see a registered tax agent if this applies to you.
Does this calculator include GST?
No. GST is a separate registration that only becomes compulsory at $75,000 turnover — or immediately, from the first dollar, for rideshare and taxi driving. See our ABN guide for how GST and ABN requirements differ.
Is this exact enough to use for my BAS or tax return?
No — it's an estimate for planning purposes only. Use a registered tax agent or the ATO's own tools when it's time to actually lodge.
What about the Medicare Levy Surcharge?
The Medicare Levy Surcharge is an extra charge (1–1.5%) for higher earners without private hospital cover, on top of the standard 2% Medicare levy. It isn't included in this calculator's results — check the ATO's Medicare Levy Surcharge page if your combined income is likely to exceed $105,000.
Sources
This calculator provides an estimate for general information only — it is not tax advice and doesn't take your full personal circumstances into account. For advice on your situation, speak to a registered tax agent, and always check current rates and thresholds at ato.gov.au.