Sole Trader Tax Calculator Australia | 2025–26

If you operate as a sole trader in Australia, your business income is taxed as personal income. There is no separate business tax rate. The calculator above estimates your income tax, Medicare levy, HELP repayments (if applicable), and quarterly PAYG instalments based on 2025–26 ATO rates. Enter your business revenue, deductible expenses, and any other income to see your estimated tax position.

How Sole Trader Tax Works in Australia

As a sole trader, you and your business are the same legal entity for tax purposes. Your net business profit (total business income minus allowable deductions) is added to any other taxable income you earn, such as employment wages or investment income. The combined total is your taxable income, and it is taxed at individual income tax rates.

You report your business income and expenses in your individual tax return using the business and professional items schedule. Unlike a company, which lodges a separate company tax return and pays a flat rate, a sole trader’s tax liability depends entirely on their personal marginal tax rate.

Key points to understand:

• No separate business tax. Your business profit flows through to your personal return.
• All income is combined. If you earn $40,000 from employment and $45,000 net profit from your sole trader business, your taxable income is $85,000.
• Deductions reduce your taxable income. Every dollar of legitimate business expense reduces the income on which you pay tax.
• Medicare levy applies. You pay the standard 2% Medicare levy on your total taxable income, subject to low-income thresholds.
• HELP debt can still apply. If you have a HELP, HECS-HELP, VSL, SFSS, or TSL debt, compulsory repayments are based on your repayment income and sit on top of your income tax estimate.

2025–26 Tax Rates for Sole Traders

Sole traders pay the same individual income tax rates as all Australian residents. For the 2025–26 financial year, the marginal rates are:

The Low Income Tax Offset (LITO) provides a further reduction of up to $700 for taxable incomes up to $66,667. The offset phases out above $37,500 and ends above $66,667.

Worked Example: $85,000 Net Profit

Suppose your sole trader business earns $120,000 in revenue with $35,000 in deductible expenses, and you have no other income or super deductions.

• Net business income: $120,000 - $35,000 = $85,000
• Tax on first $18,200: $0
• Tax on $18,201 to $45,000: $26,800 x 16% = $4,288
• Tax on $45,001 to $85,000: $40,000 x 30% = $12,000
• Income tax before LITO: $16,288
• LITO: $0 (income above $66,667)
• Medicare levy: $85,000 x 2% = $1,700
• Total tax: $17,988
• Effective tax rate: 21.16%
• After-tax income: $67,012

At an $85,000 taxable income, your marginal rate is 30% (plus 2% Medicare). Every additional dollar of business profit costs you 32 cents in tax.

PAYG Instalments for Sole Traders

Once your tax return shows business or investment income, the ATO may enter you into the PAYG instalment system. This means you pay tax in four quarterly instalments throughout the year, rather than a single lump sum at tax time.

The ATO calculates your instalment amount or rate based on your most recent tax return. You can choose between two methods:

• Instalment amount method. The ATO tells you the dollar amount to pay each quarter. Simpler, but may not reflect current-year income changes.
• Instalment rate method. The ATO provides a percentage rate, and you apply it to your actual quarterly income. More work, but more accurate if your income varies.

Using the worked example above ($85,000 taxable income, $17,988 total tax):

• Quarterly PAYG instalment: approximately $4,497
• Due dates: 28 October, 28 February, 28 April, and 28 July

Setting aside money for tax is one of the biggest adjustments when moving from employment to sole trading. A practical approach is to transfer your estimated monthly tax provision (approximately $1,499 per month in this example) into a separate high-interest savings account each month.

Tax Deductions for Sole Traders

The ATO allows you to deduct expenses that are directly related to earning your business income. Maximising legitimate deductions is the most effective way to reduce your tax bill. Common sole trader deductions include:

• Home office expenses. If you work from home, you can claim a portion of rent or mortgage interest, electricity, internet, phone, and office supplies. The ATO offers a fixed rate method (67 cents per hour for 2025–26) or the actual cost method.
• Vehicle and travel. Business-related travel including fuel, registration, insurance, and depreciation. Keep a logbook for at least 12 continuous weeks to establish your business-use percentage.
• Tools and equipment. Items costing $300 or less can be immediately deducted. More expensive items are depreciated over their effective life.
• Professional development. Courses, conferences, subscriptions, and books related to your business activity.
• Insurance. Business insurance premiums including public liability, professional indemnity, and income protection (the income protection component is deductible).
• Accounting and legal fees. Tax agent fees, bookkeeping software subscriptions, and business-related legal costs.
• Phone and internet. The business-use proportion of your phone and internet bills.
• Depreciation. The decline in value of business assets like computers, furniture, and vehicles.

You must keep records of all expenses for at least five years. The ATO can request evidence of any deduction claimed, and penalties apply for unsubstantiated claims.

Super Contributions as a Tax Strategy

Unlike employees who receive compulsory super guarantee contributions from their employer, sole traders are not required to pay super for themselves. However, making personal super contributions and claiming a tax deduction is one of the most effective tax planning strategies available.

For 2025–26, the concessional contributions cap is $30,000 per year. This includes any employer contributions from other employment plus your personal deductible contributions.

Worked Example: $85,000 Income with $20,000 Super Contribution

Using the same $85,000 net business income:

• Without super deduction: taxable income $85,000, total tax $17,988
• With $20,000 super contribution: taxable income $65,000, total tax approximately $11,563
• Tax saving: approximately $6,425

The $20,000 is taxed at 15% inside your super fund ($3,000), so the net benefit is $6,425 - $3,000 = $3,425 in combined savings, plus you have $20,000 more in retirement savings.

To claim the deduction, you must:

1. Make the contribution to a complying super fund before 30 June.
2. Lodge a “Notice of intent to claim a deduction” (NAT 71121) with your super fund.
3. Receive an acknowledgement from the fund before lodging your tax return.

If you have unused concessional cap amounts from previous years (carry-forward rule), you may be able to contribute more than $30,000 in a single year, provided your total super balance was below $500,000 on 30 June of the previous year.

GST Obligations

GST is separate from income tax but affects most sole traders. You must register for GST if your annual GST turnover (gross business income, not profit) is $75,000 or more. Registration is optional if you are below this threshold but can be beneficial if most of your clients are GST-registered businesses.

Once registered, you:

• Charge 10% GST on your taxable sales
• Claim GST credits on business purchases
• Lodge a Business Activity Statement (BAS) quarterly or monthly
• Pay the net GST amount (GST collected minus GST credits) to the ATO

GST does not appear in your income tax calculation because it is reported separately on your BAS. When entering business income in the calculator above, use your income excluding GST. Use our GST Calculator to work out GST amounts, or our BAS Calculator to estimate your quarterly BAS GST liability.

Sole Trader vs Company Tax

Many sole traders wonder whether incorporating as a company (Pty Ltd) would reduce their tax bill. The comparison depends on your income level and what you do with the profits.

A sole trader earning under $135,000 in taxable income generally pays a lower effective tax rate than a company, because the tax-free threshold and lower brackets reduce the average rate. Above $135,000, a company structure may offer advantages, but you still need to extract the money as salary (taxed at individual rates) or dividends (with franking credits).

The break-even point depends on your personal circumstances. Most accountants suggest considering incorporation when your consistent net business profit exceeds $120,000 to $150,000 and you can leave some profit in the company rather than drawing it all out.

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