It’s one of the most common questions Australians ask their tax agent. The honest answer depends on whether you’re lodging the return yourself or through a registered tax agent.

The Australian income year runs from 1 July to 30 June. If you lodge yourself, you have until 31 October to lodge that year’s return. Most people stop reading there. That’s the date they put in their calendar, and it’s the one they hit (or miss) every year.

There’s a second lodgement date available to most individual taxpayers. It sits six and a half months later, and it’s legitimate, ATO-sanctioned, and used by tax agents every day. The catch is that you have to do one thing before 31 October to unlock it.

Here are both dates, the concessions sitting alongside them, and what happens if you miss every one.

At a glance

• The standard deadline: 31 October. If you lodge through myGov or on paper, this is your date.
• The agent deadline: 15 May the following year. Available if you’re on a registered tax agent’s books by 31 October.
• The 5 June concession. A no-penalty grace period after 15 May, provided any tax owed is also paid by that date.
• The good-standing rule. One overdue prior-year return cancels the extension. Your current return then defaults to 31 October.
• The penalty if you miss every deadline. Failure to Lodge: one penalty unit per 28 days, capped at five units.
• Tax debts can be paid in instalments. The ATO offers payment plans, typically up to 24 months for individuals.

1. The 31 October deadline

If you’re lodging your own tax return through myGov or on paper, your return is due by 31 October following the end of the income year.

• If 31 October falls on a weekend or public holiday, the deadline shifts to the next business day.
• Self-lodgers don’t get an automatic extension. There’s no quiet grace period.
• The ATO begins processing returns from 1 July, but pre-fill data from employers, banks, health funds and Centrelink is generally not complete until mid to late July. Lodging too early increases the chance of an amendment later.

Bottom line: 31 October is the only deadline if you’re going it alone. Mark it. Lodge in late July or August once pre-fill is complete.

2. The 15 May deadline (registered tax agent)

If you engage a registered tax agent before 31 October, you generally have until 15 May the following year to lodge. That’s six and a half extra months on the same income year. Same return, much longer to file.

• You must be on the agent’s books before 31 October to qualify. Signing up with an agent in November doesn’t unlock the extension for the prior year.
• Only tax practitioners registered with the Tax Practitioners Board (TPB) can lodge tax returns for fee or extend your deadline. The TPB register is publicly searchable.
• Bookkeepers, financial planners and accountants without TPB registration cannot lodge a return on your behalf, regardless of qualifications.

Bottom line: The agent extension is the single biggest unlock most individual taxpayers don’t know about. Engaging a tax agent before 31 October is the only thing standing between you and an extra six months.

3. The 5 June concession

Sitting alongside the 15 May deadline is a concession that gives you a small additional window of grace, but only on specific conditions.

• If you lodge by 5 June and pay any tax owed by 5 June, the ATO will not apply failure-to-lodge penalties for being past 15 May.
• It’s available for individual, partnership and trust returns. Large and medium taxpayers and consolidated group head companies don’t get it.
• This isn’t an extension you apply for. It’s a no-penalty period the ATO runs automatically.
• Both lodgement and payment have to be in by 5 June. Lodging on 5 June but paying tax owed a week later doesn’t qualify.

Bottom line: Treat 5 June as a backstop, not a planning target. If life genuinely got in the way after 15 May, this is your last clean exit before penalties start running.

4. The good-standing rule

The 15 May extension is conditional. It applies only if you’re in good standing with the ATO, and the main thing that means is no prior-year tax returns outstanding.

• If you have one overdue return from a previous year (any year), the agent extension is automatically lost. Your current return defaults back to the 31 October deadline.
• This applies whether or not you’ve engaged an agent. Engaging an agent doesn’t restore the extension on its own.
• The fix is to lodge any outstanding prior-year returns first. Once your record is clean, the extension applies to the current year’s return.
• A tax agent can also help you catch up on multiple back years and negotiate with the ATO on any penalties that have already been raised.

Bottom line: Years of compliance protect this year’s extension. If you’re uncertain whether you have outstanding returns, your tax agent can pull your lodgement history from the ATO.

5. What happens if you miss every deadline

Without a valid extension, the Failure to Lodge on Time penalty applies once your deadline has passed.

• The penalty is one penalty unit for every 28 days the return is overdue, capped at five units.
• The penalty unit value is set by legislation and indexed periodically. The current value is published by the ATO.
• For repeat offenders and larger entities, the ATO can apply higher base penalty multiples.
• Generally the ATO doesn’t penalise isolated late lodgements. It will usually issue a warning by phone or in writing first, and you can request remission once a penalty is raised.
• On top of the FTL penalty, the General Interest Charge (GIC) applies to any unpaid tax. GIC compounds daily and is not tax-deductible.

Bottom line: The cost of missing every deadline is much higher than the cost of engaging an agent in October.

When you owe tax (and might want to use the extension)

The two deadlines suit different situations.

If you’re expecting a refund

• Lodge as early as the data allows. The refund only arrives once your return is processed.
• Most refunds for straightforward returns are processed within two weeks of lodgement, often faster electronically.

If you’re expecting a tax bill

• The extension genuinely helps with cashflow. Lodging on 15 May means the tax debt isn’t formally due until the lodgement-based payment date, typically a few weeks later.
• Some clients use the extra months to hold the funds in an offset account or earn interest, then pay on the due date.
• Important: lodging late doesn’t escape tax. The amount you owe is the amount you owe. The extension shifts the deadline, not the amount.

If you can’t pay in full when the return is lodged

• The ATO can usually negotiate a payment plan for individual tax debts. Plans typically run up to 24 months.
• You must keep all future tax obligations current while on the plan.
• GIC accrues on the unpaid debt and is not tax-deductible.
• Breaching a payment plan (missing an instalment, falling behind on future obligations) generally cancels it and triggers full collection.

Bottom line: Use the extension when you owe tax. Lodge earlier when you expect a refund. The extension and a payment plan are both tools your tax agent can use; the earlier you talk to them, the more options you have.

When to start preparing your return

• The ATO begins processing from 1 July, but pre-fill data is usually only complete by mid to late July.
• Lodging too early increases the chance of mismatched data and amended returns.
• The best window to engage a tax agent for the current year’s return is between July and September. Earlier means more agent attention; later means working through the October deadline crunch.
• If you’re expecting a refund and your income is straightforward, late July is usually the sweet spot.

Two deadlines, three concessions, one penalty regime

The Australian tax lodgement framework looks complicated and isn’t. There are two real deadlines (31 October self-lodge, 15 May with a registered agent), one concession that softens the second deadline (5 June), one rule that can cancel the extension (a prior-year outstanding return), and one penalty regime if you miss every deadline (FTL plus GIC).

Used well, the two-deadline system gives you flexibility that self-lodgers don’t have. The single thing that unlocks it is getting onto a registered tax agent’s books before 31 October.

FabTax lodges tax returns for individuals, property investors and small business owners across Australia. We do tax properly. That’s the whole promise.

Talk to our team about getting on our books before 31 October.

The information provided is general in nature and does not constitute financial or tax advice. For advice specific to your situation, please consult a qualified professional. Flinders Accounting & Business Services Pty Ltd, Registered Tax Agent.