Second Job Tax Calculator Australia 2025-26

The biggest myth about second jobs is that they're taxed twice, or at some special penalty rate. They're not. The ATO adds up your income from all your jobs and taxes the total once, using the same marginal brackets that apply to everyone. Your second job feels like it's taxed more because it stacks on top of your first job — so every dollar of it sits in your highest tax bracket.

Why a second job can leave you with a tax bill

The real culprit is PAYG withholding, not the tax rate. Each employer withholds tax as if they're your only job. If you claim the tax-free threshold on both jobs, each one treats your first $18,200 as tax-free — but you only get one tax-free threshold across all your income. The result is too little tax withheld during the year, and a bill when you lodge your return.

The fix: claim the threshold on one job only

Claim the tax-free threshold on your higher-paying job, and don't claim it on your second job. The second employer then withholds at the "no tax-free threshold" rate, which keeps your withholding much closer to the tax you actually owe. You can change this any time by giving your employer a new Withholding Declaration.

2025-26 tax brackets

• $0 – $18,200: 0% (tax-free threshold)
• $18,201 – $45,000: 16%
• $45,001 – $135,000: 30%
• $135,001 – $190,000: 37%
• $190,001+: 45%
• Plus 2% Medicare levy on all taxable income