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 for Australian tax returns applies to individuals who lodge their own return without using a registered tax agent. If you engage a registered tax agent, you automatically receive an extended deadline, typically to May 15 of the following year (and sometimes later, depending on the agent’s lodgment program with the ATO).

Who Must Lodge by October 31

According to the Australian Taxation Office, the October 31 deadline applies to individuals who prepare and submit their own tax return through myTax or paper lodgment. This includes anyone who:

  • Lodges their return directly via the ATO’s myTax online portal
  • Submits a paper tax return by mail
  • Has not engaged a registered tax agent by October 31

If you are required to lodge a tax return for the financial year ending June 30, and you choose to self-lodge, your return and any tax owed must be submitted and paid by October 31. Missing this deadline may result in penalties and interest charges from the ATO.

Who Gets an Automatic Extension

Engaging a registered tax agent before the October 31 deadline gives you an automatic extension. Registered tax agents operate under lodgment programs approved by the ATO, which provide concessional due dates ranging from March 15 to May 15 of the following year (some agents have even later dates depending on their agreement with the ATO).

You do not need to apply for this extension separately. Once you appoint a registered tax agent and provide them with your tax information, the agent notifies the ATO, and your lodgment obligation is transferred to the agent’s program timeline.

Who Needs a Registered Tax Agent

You are not legally required to use a tax agent. Most Australian taxpayers with straightforward income and deductions (salary or wages from one or two employers, standard deductions, and basic offsets) can comfortably self-lodge using myTax. The ATO pre-fills most of your information, including income from employers, banks, health funds, and government payments.

However, you may benefit from using a registered tax agent if you have:

  • Multiple income sources (salary, rental property income, dividends, capital gains, sole trader or partnership income)
  • Complex deductions (work-related expenses across multiple categories, investment property claims, self-education expenses, motor vehicle claims)
  • Capital gains tax (CGT) events during the year (property sales, share sales, crypto disposals)
  • Foreign income or foreign tax offsets
  • Business or sole trader income requiring detailed record reconciliation
  • HECS/HELP debt that affects your repayment obligations
  • Previous ATO audits or amended assessments

Read also: How Australian Income Tax Brackets Work: The Marginal Rate System Explained Step by Step

A registered tax agent is trained to identify deductions you may overlook, correctly apply CGT discount rules, manage franking credits, and reduce your risk of triggering an ATO review. Fees paid to a registered tax agent for preparing your tax return are tax-deductible in the year you pay them.

What Happens If You Miss the Deadline

If you self-lodge and miss the October 31 deadline without a valid reason, the ATO may issue a failure-to-lodge (FTL) penalty. The penalty amount depends on the size of your tax debt and how late you lodge. For individuals, FTL penalties start at one penalty unit per period of delay (currently $313 per 28-day period, as of August 2026, subject to annual indexation).

If you owe tax and lodge late, the ATO will also charge the general interest charge (GIC) on the unpaid amount from November 1 until the debt is paid. The GIC compounds daily.

If you know you will miss the October 31 deadline and have not yet engaged a tax agent, contact the ATO as soon as possible. You can request a deferral or arrange a payment plan if you owe tax. The ATO may remit penalties if you have a reasonable excuse (serious illness, natural disaster, or other circumstances beyond your control).

How to Check If Your Tax Agent Is Registered

Only registered tax agents and BAS agents are authorised to lodge tax returns on behalf of clients and provide tax advice for a fee. You can verify an agent’s registration on the Tax Practitioners Board (TPB) register at tpb.gov.au. A registered tax agent will have a unique registration number and must display their TPB registration details on their website and correspondence.

Do not use unregistered preparers. Unregistered individuals who charge fees to prepare tax returns operate illegally, and you remain personally liable for any errors or omissions in your return, even if the preparer made the mistake.

Key Takeaway

If you self-lodge your Australian individual tax return, your deadline is October 31. If you engage a registered tax agent, your deadline extends to at least May 15 the following year. You are not required to use an agent, but one may be worthwhile if your tax affairs involve multiple income streams, deductions, capital gains, or business income. Always verify your agent is registered with the Tax Practitioners Board, and contact the ATO early if you cannot meet your lodgment deadline.

For current lodgment deadlines, visit ato.gov.au or consult a registered tax agent.