EOFY Deadline: What Happens If You Lodge Your Tax Return Late in Australia

Every year, thousands of Australians miss the deadline to lodge their tax return – and many don’t realise the consequences until an ATO penalty notice lands in their inbox. If you’re wondering what happens when you lodge your tax return late in Australia, the answer depends on how late you are, whether you owe money, and what steps you take to fix it.

Disclaimer: This article provides general information only and does not constitute tax advice. Consult a registered tax agent for advice specific to your circumstances.

This guide covers the key deadlines, the penalties you could face, how to avoid them, and what to do if you’ve already missed the boat.

Key Tax Return Deadlines in Australia

The Australian financial year runs from 1 July to 30 June. Once the financial year ends, you have a limited window to lodge your tax return:

• 31 October – Deadline for individuals who self-lodge their tax return (either on paper or through myTax on the ATO website).
• Extended deadlines (up to 15 May the following year) – If you use a registered tax agent, you may be eligible for an extended lodgement deadline. The exact date depends on your circumstances and your agent’s lodgement program with the ATO.
• Earlier deadlines may apply – If you have prior year returns that are overdue, the ATO may require you to lodge by 31 October regardless of whether you use a tax agent.

The most common mistake is assuming you have until 31 October if you’ve engaged a tax agent late in the year. Tax agents have their own schedules and lodgement programs, so engaging one in September doesn’t automatically guarantee an extension.

What Happens If You Lodge Your Tax Return Late

The ATO takes late lodgement seriously. Here’s what you face:

Failure to Lodge (FTL) Penalty

If you’re required to lodge a tax return and don’t do so by the due date, the ATO can impose a Failure to Lodge penalty. The penalty is calculated as follows:

• $313 for each 28-day period (or part thereof) that the return is overdue
• Up to a maximum of five periods, making the maximum FTL penalty $1,565
• The penalty amount is based on the penalty unit value, which is indexed and may change each year

The penalty applies per overdue return. If you have multiple years outstanding, each year attracts its own FTL penalty – and those amounts compound quickly. Two years overdue could mean penalties exceeding $3,000 before you’ve even calculated the tax you owe.

General Interest Charge (GIC)

If you owe tax and pay it late, the ATO charges the General Interest Charge on the outstanding amount. The GIC rate is set quarterly and is based on the 90-day bank bill rate plus 7 percentage points – which means it’s significantly higher than a standard loan rate. The GIC compounds daily, so the longer you wait to pay, the more it costs.

Default Assessment

If you don’t lodge your return and the ATO loses patience, they can issue a default assessment. This is where the ATO estimates your income and tax liability based on available information – employer reports, bank data, third-party data matching – and sends you a bill.

Default assessments are almost always unfavourable. The ATO doesn’t have visibility into your deductions, so they tend to assess your income at the gross amount with minimal or no deductions applied. You’ll owe more tax than you should, and you’ll still need to lodge the actual return to correct it. Until you do, the default assessment stands.

Other Consequences

Beyond formal penalties, lodging late can create a cascade of problems:

• Delayed refunds – If the ATO owes you money, you won’t receive it until you lodge.
• Impact on future dealings – A history of late lodgement can affect your standing with the ATO. If you’re a sole trader or run a business, this can complicate future interactions.
• Loss of deductions – As time passes, receipts fade, memories blur, and records go missing. The longer you wait to lodge, the more likely you are to miss legitimate deductions simply because you can’t find the documentation.

How to Avoid Late Lodgement Penalties

Prevention is always cheaper than penalties. Here’s how to stay on the right side of the deadline:

Lodge on Time

The simplest solution. The ATO’s myTax system is free and pre-fills much of your return with data from employers, banks, health funds, and government agencies. If your tax affairs are straightforward, you can complete and lodge your return in under an hour.

Use a Registered Tax Agent

If your finances are more complex – multiple income sources, investment properties, a business, or significant deductions – engage a registered tax agent. Beyond their expertise, the main practical benefit is the extended lodgement deadline. Most tax agents can lodge your return well beyond the 31 October deadline under the ATO’s lodgement program, giving you several additional months.

The key is to engage your tax agent early. Don’t wait until October to make an appointment – by then, most agents are fully booked and may not be able to take you on under their extended deadline program.

Contact the ATO if You’re Struggling

If you know you’re going to miss the deadline, contact the ATO before it passes. The ATO has provisions for people experiencing hardship – financial difficulties, natural disasters, serious illness, or other extenuating circumstances. In many cases, they’ll work with you on a payment plan or adjust the lodgement deadline rather than imposing penalties.

You can contact the ATO on 13 28 61 for individual tax enquiries.

What to Do If You’ve Already Lodged Late

If you’ve already missed the deadline, don’t put it off further. Every additional 28-day period adds another $313 to your FTL penalty, so acting quickly limits the damage.

Lodge as Soon as Possible

The single most important thing you can do is lodge your return immediately. The FTL penalty is based on how late you are, so every day you delay adds to the cost. Even if you can’t pay the tax you owe right now, lodging the return stops the FTL penalty clock.

Contact the ATO

If you’ve been issued a penalty, you can request that the ATO remit (reduce or cancel) it. The ATO considers remission requests on a case-by-case basis, taking into account factors such as:

• Your compliance history (first-time offenders are treated more leniently)
• Whether there were circumstances beyond your control
• Whether you took action to lodge as soon as you could
• Whether you’ve brought all your lodgements up to date

Set Up a Payment Plan

If you owe tax and can’t pay the full amount immediately, the ATO offers formal payment plans. You can set one up online through myGov or by calling the ATO. Payment plans allow you to pay your debt in instalments while reducing the impact of the General Interest Charge. The ATO is generally accommodating for people who engage proactively – it’s the people who go silent that face the harshest outcomes.

Lodge All Outstanding Returns

If you have multiple years outstanding, lodge all of them at once. The ATO views this favourably and may be more willing to remit penalties if you demonstrate a genuine effort to catch up. A tax agent can help you work through multiple years efficiently.

How to Prevent Late Lodgement Next Year

The most common reason people lodge late isn’t procrastination – it’s that they’re not prepared. When tax time arrives and your records are scattered across bank statements, email inboxes, and faded paper receipts, the task feels overwhelming. So you put it off. And then you put it off again.

The fix is tracking your expenses throughout the year, not just in the weeks before the deadline. For a complete preparation guide, see our EOFY tax checklist for freelancers.

Taxr makes year-round tracking effortless. Scan any receipt with your phone’s camera and the AI instantly extracts the date, amount, vendor name, and GST. Every expense is categorised and stored securely in the cloud. When tax time arrives, export a clean, categorised report in seconds and hand it straight to your accountant – or use it to lodge your own return through myTax.

No scrambling. No shoeboxes. No penalties. Just a clean lodgement, on time, every year.

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