Second job vs ABN side hustle calculator

Why the total is always the same

Australia taxes your total taxable income, not each income stream separately. Salary, wages and sole trader net profit all land in the same pot and are taxed at the same marginal rates. There is no separate ABN tax rate, and no second tax-free threshold for a second income.

The ATO puts it plainly: your income may come from one or more payers at the same time, and payers include employers, government agencies, or work you do as a sole trader. One threshold, shared across all of them.

So why does a second job "feel" taxed more?

Because you only claim the tax-free threshold from one payer — normally the one paying you the most. Your second payer therefore withholds at the no tax-free threshold rate, taking tax from the very first dollar. That looks punishing on the payslip.

But withholding isn't tax. It's a prepayment. At lodgment the ATO works out what you actually owe on your total income and squares it up — which is why people with a modest second job so often get money back. The ATO's own worked example has someone earning $16,000 in retail and $10,000 in a restaurant with $1,716 withheld from the second job, ending up with a total tax bill of $548 and a $1,168 refund.

The mistake to avoid is the opposite one: claiming the threshold from both payers. Then roughly $18,200 of your income gets treated as tax-free twice, nowhere near enough is withheld, and the shortfall arrives as a bill.

The real difference: cash flow

With an ABN side hustle, nobody withholds anything. Every dollar a client or platform pays you lands in your account in full — including the part that belongs to the ATO. Nothing about that is worse for tax, but it is much easier to spend money you don't actually have.

That's what the set-aside figure above is for. Move that percentage of every payment into a separate account the day it arrives, and tax time stops being an event.

One more thing to plan for: once the hustle is established, the ATO will put you into PAYG instalments — automatically, once your return shows instalment income of $4,000 or more, tax payable of $1,000 or more, and notional tax of $500 or more. The first instalments often arrive around the same time as the bill for the year that triggered them.

How this is calculated

Your liability is income tax plus the Medicare levy on your combined income, plus any compulsory HELP/HECS repayment. That figure doesn't change between the three options — only the withholding does.

Withholding is approximated. Real PAYG withholding follows the ATO's withholding schedules, which round to whole-dollar amounts per pay period and apply their own coefficient tables. Here we model annual tax with the tax-free threshold (for your main job, and for the "claimed at both" scenario) and without it (for a correctly-declared second job). That's close enough to show you the shape of the outcome, but don't treat the dollar figures as exact.

The calculation also ignores deductions, offsets such as the low income tax offset, the Medicare levy surcharge, HELP indexation, and anything specific to your circumstances.

Frequently asked questions

Is my second job taxed at a higher rate?

No. All your income is added together and taxed at the same marginal rates at the end of the year. What's different is the withholding: because you only claim the tax-free threshold from one payer, your second payer withholds at the 'no tax-free threshold' rate. That's a higher rate of withholding, not a higher rate of tax — and it usually means a refund, not a loss.

Why does claiming the tax-free threshold at both jobs cause a debt?

Because each payer then withholds as if the first $18,200 of your income were tax-free — so between them they leave about $18,200 of your income untaxed twice. You only get one tax-free threshold, so at lodgment the shortfall becomes a bill. The ATO's guidance is to claim it from the payer who pays you the highest salary or wage.

Does an ABN side hustle get its own tax-free threshold?

No. The ATO treats sole trader work as another payer for threshold purposes — your income may come from one or more payers at the same time, and payers include employers, government agencies, or work you do as a sole trader. There is one tax-free threshold across all of them, and it's normally already used by your main job.

Is an ABN side hustle worse for tax than a second job?

The tax is identical. The cash flow is not. With a second job, tax is withheld from every pay, so most of what you owe is already covered by the time you lodge. With an ABN, nothing is withheld — the full amount lands in your account and the bill arrives later. That's a budgeting problem, not a tax problem, and setting money aside from every payment solves it.

What about GST and an ABN?

GST is separate from income tax and only becomes compulsory at $75,000 turnover — except for ride-sourcing (carrying passengers for a fare), where you must register from the first dollar. Food delivery is not passenger transport, so the ordinary $75,000 threshold applies to it.

Will I have to pay PAYG instalments?

Possibly, once the side hustle is established. The ATO enters you into PAYG instalments automatically when your latest return shows instalment income of $4,000 or more, tax payable of $1,000 or more, and notional tax of $500 or more. The instalments for the new year often arrive around the same time as the bill for the year that triggered them.

How accurate is the withholding figure?

It's an estimate. Real PAYG withholding follows the ATO's withholding schedules, which round to whole-dollar amounts per pay period and use their own coefficient tables. This calculator models annual tax with and without the tax-free threshold instead, which is close enough to show you the shape of the outcome but shouldn't be used as an exact figure.