If you had two or more employers during FY2025-26, myTax will generally pull in every income statement your TFN is linked to automatically — but a tax bill often shows up for exactly this group, because the tax-free threshold and standard withholding rates only work correctly if just one employer applies them. This is one of the tax-time surprises AusTax AI hears about most from people juggling two jobs for the first time.
How does myTax combine multiple income statements?
Once you've confirmed your TFN details and each employer has finalised their Single Touch Payroll data, myTax's prefill lists every income statement linked to you for the year, tagged by employer name, and totals the wages and tax withheld across all of them automatically. AusTax AI's own income dashboard does the same aggregation across every employer you add, specifically so a missing or pending income statement doesn't get overlooked before you lodge. You don't need to add each job manually if the data has come through — you're mainly checking that every employer you worked for actually appears, and that each one shows as "tax ready" rather than pending (see our guide on income statements showing "not tax ready" if one is missing that status).
Why does having two jobs so often lead to a tax bill?
When you start a job, the TFN declaration asks whether you want to claim the tax-free threshold from that payer — the first $18,200 of income taxed at 0%. It's designed to be claimed from one employer only, usually your highest payer. If you accidentally tick "yes" at a second job too, each employer withholds tax as though you only earn from them, giving you the tax-free threshold's benefit twice during the year. Once myTax combines your actual total income, the real marginal rate applies to the whole amount — and the gap between what was withheld and what's actually owed shows up as a bill.
A simplified worked example
| Job A (main) | Job B (second) | |
|---|---|---|
| Tax-free threshold claimed? | Yes | Yes (should be No) |
| Employer withholds as if... | Sole income source | Sole income source |
| Effect on withholding | Roughly matches Job A's own tax | Too low for the combined income |
Because both employers independently withhold as if their pay was your only income, the combined withholding across both jobs ends up lower than what your combined income actually owes once it's all taxed together at your real marginal rate. This is a mechanical effect of how withholding works, not a sign anything was done incorrectly on the return itself.
How do I avoid this next financial year?
If you're taking on a second job, tell that employer not to claim the tax-free threshold on your TFN declaration — myTax itself can't fix withholding that already happened during the year, only the final calculation once everything's combined. If you're not sure whether you accidentally claimed it twice, check your income statements: an employer withholding very little tax relative to your pay is the typical sign.
Quick checklist
- Confirm every employer you worked for during the year appears in your prefill
- Check each income statement shows "tax ready" before you rely on the totals
- If you're surprised by a tax bill with two jobs, it's very often the tax-free threshold claimed at both — not an error in the return itself
- For next year, only claim the tax-free threshold at your highest-paying employer
If you also have a HECS-HELP debt, having two employers can affect how much was withheld for that too — see our guide on the HECS-HELP question in myTax for how that reconciles. And if you're newly employed and haven't yet applied for a TFN, our guide on applying for a TFN in Australia covers that first step.
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*This is general information only, not personal tax advice. Your specific withholding and tax position depends on your full income for the year — confirm with a Registered Tax Agent if you're unsure.*
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*Disclaimer: This is general information only and does not constitute personal tax advice. Consult a registered tax agent for advice tailored to your specific situation. Always verify against the latest ATO guidelines at ato.gov.au.*