This article provides general information only and does not constitute personal financial advice. It has been prepared without taking into account your objectives, financial situation or needs. Before acting on any information in this article, you should consider whether it is appropriate for you and seek advice from a licensed financial adviser if necessary.

The October 31 deadline is the date by which most Australians must lodge their individual tax return for the previous financial year. If you lodge through a registered tax agent, you typically receive an extended deadline, but for those lodging directly through myTax or paper forms, October 31 is final. Missing it can result in penalties and interest charges from the ATO.

Before you hit submit, work through this checklist to ensure your return is complete, accurate and maximises your legitimate entitlements.

1. Confirm all income statements appear in myGov

Log into myGov and link to the ATO if you have not already done so. The ATO pre-fills income information from employers, banks, government agencies and investment platforms. Check that every source of income you earned during the financial year appears in the pre-fill data. If a payment summary or statement is missing, contact the payer directly or manually add the income. According to the ATO, lodging with incomplete income is one of the most common errors (ATO, 2026).

2. Verify bank interest and dividend statements

Interest from savings accounts, term deposits and dividends from Australian shares (including franking credits) should appear automatically in myTax, but timing matters. Some financial institutions report late. Cross-check the pre-filled amounts against your own records or annual statements. Franking credits can materially reduce your tax liability or generate a refund, so ensure the franked amount and franking credit are both captured correctly.

3. Review investment property income and expenses

If you own an investment property, gather rental income statements and all deductible expenses: loan interest, property management fees, council rates, insurance, repairs and maintenance, depreciation schedules, and strata levies. Negative gearing allows you to offset a net rental loss against other income, so accurate record-keeping is essential. Capital works deductions (building depreciation) and plant and equipment depreciation require a quantity surveyor’s report if the property was purchased after the relevant legislative changes. Keep invoices and receipts for at least five years.

4. Confirm deductible superannuation contributions

If you made personal (non-concessional) contributions to your super fund and intend to claim a tax deduction for them, you must lodge a Notice of Intent to Claim form with your fund before lodging your tax return or before the end of the financial year (whichever is earlier). Without that notice, the deduction is disallowed. Check your super fund statement to confirm the contribution was received and processed as a concessional (deductible) contribution. The annual concessional contributions cap is $30,000 (as of the 2025-26 financial year, subject to indexation; verify current limits at ato.gov.au).

The ATO requires written evidence (receipts, invoices, logs) for most work-related expense claims above $300. Common deductions include home office running costs (if you worked from home), car expenses (logbook or cents-per-kilometre method), uniforms, professional memberships, and self-education directly related to your current employment. The ATO’s record-keeping requirements are strict. Claims without substantiation, or claims for private expenses presented as work-related, are a red flag for audit.

Read also: Australian Tax Lodgment Deadline October 31: Who Needs a Registered Agent

6. Check for capital gains or losses

If you sold shares, investment property, cryptocurrency, or other capital assets during the financial year, you must report the capital gain or loss. For assets held 12 months or more, Australian residents receive a 50 per cent CGT discount on the net capital gain. Losses can be offset against gains in the same year or carried forward. The cost base includes the purchase price, transaction costs, and certain holding costs. For property, include stamp duty and legal fees. For crypto, keep detailed transaction records as the ATO data-matches exchange reports.

7. Verify private health insurance statement

Your private health insurer provides an annual statement showing the tier of cover you held and the number of days covered. This information determines whether you are liable for the Medicare levy surcharge (if your income exceeds the relevant threshold and you do not hold adequate hospital cover). It also affects your entitlement to the private health insurance rebate. The ATO pre-fills this data, but check it matches your own records, especially if you changed funds or policies mid-year.

8. Review HECS-HELP debt status

If you have a HECS-HELP debt, compulsory repayments apply once your income exceeds the minimum repayment threshold (approximately $54,435 for the 2025-26 income year, indexed annually). The ATO calculates the repayment as a percentage of your total taxable income, not just the amount above the threshold. If your employer has not withheld enough HECS-HELP repayment during the year, you may face a tax bill. Check your notice of assessment from prior years to confirm your outstanding debt balance and verify the repayment amount.

9. Confirm Medicare levy and surcharge position

Most Australian residents pay the Medicare levy (2 per cent of taxable income). Low-income earners may qualify for a reduction or exemption. The Medicare levy surcharge (an additional 1 to 1.5 per cent) applies to individuals and families above certain income thresholds who do not hold private hospital insurance. Verify your income level, exemption status, and whether you held adequate cover for the full year.

10. Check spouse and dependent details

If you are claiming the spouse tax offset, the low-income spouse tax offset, or offsets for dependents, ensure the details are current and accurate. The spouse’s income must fall below the relevant threshold, and you must not be living separately or permanently. For dependent (invalid and carer) tax offset claims, medical evidence or carer payment details may be required.

Final checks before lodging

Review your refund or debt estimate in myTax. A surprisingly large refund or debt may indicate a data-entry error. Double-check that all income is reported, all eligible deductions are claimed with substantiation, and that offsets and adjustments are correct. Lodge early if you are expecting a refund. If you owe tax, lodge by October 31 to avoid failure-to-lodge penalties, and pay by the due date on your notice of assessment to avoid interest charges.

If your tax affairs are complex (multiple income sources, investment properties, capital gains, business income, foreign income), consider engaging a registered tax agent. Their lodgment deadline extends well beyond October 31, giving you more time and professional guidance. Visit ato.gov.au or moneysmart.gov.au for further detail and updates.