When Should You File Your Tax Return in Australia? Key Dates and Rules

Lodging a tax return every year is compulsory for most people earning money in Australia – and it doesn't need to be a stressful experience. By being responsible and staying on top of the tax return deadlines, you can make your annual tax experience an easy and straightforward experience.

The most important date in the Australian tax calendar is 31 October. That is the standard deadline for Australians who lodge their own tax return. If you miss the deadline, late lodgement penalties may apply. Many taxpayers choose to use a registered tax agent instead, as eligible tax agent clients may qualify for later lodgement dates and professional support throughout the process.

Beyond October 31, there is a parallel system for tax agent clients, a separate set of rules for businesses and BAS lodgements, and a growing number of people each year who need to know what happens if they lodged too early, made a mistake, or simply cannot pay what the ATO says they owe. This guide covers all of it.

What is the Tax Return Deadline in Australia?

For most Australians lodging their own 2025-26 tax return, the standard lodgment deadline is 31 October 2026.

The Australian income year runs from 1 July to 30 June. Once the 2025-26 income year ends on 30 June 2026, taxpayers who need to lodge can generally submit their return from 1 July. The ATO recommends waiting until your income information is complete and tax ready before lodging.

Self-Lodgers: 31 October Deadline

If you prepare and lodge your tax return by yourself, your tax return is generally due by 31 October.

If 31 October falls on a weekend, the due date moves to the next business day. If you are unable to lodge by the deadline, it is important to seek professional assistance as soon as possible.

Tax agent clients may have a later lodgement deadline

Registered tax agents operate under an ATO lodgment program that allows eligible clients to lodge later than the standard 31 October deadline.

The exact lodgment date depends on factors such as your tax history, whether you have outstanding prior-year returns, when you were added to your tax agent's client list and your individual circumstances.

If you plan to use a registered tax agent, the ATO generally requires you to engage them before 31 October.

Need more time to lodge your tax return?

If you haven't lodged your 2026 tax return, H&R Block may be able to help you get more time.

Eligible taxpayers who register with H&R Block before 31 October may qualify for a later lodgment date under the ATO's tax agent lodgment program.

Check your eligibility and register for a tax return deadline extension.

Business Owners: BAS and Other Deadlines

Business owners face a calendar of compliance obligations beyond the personal income tax return. These are covered in detail in the Business and BAS Deadlines section below, but the headline dates are: quarterly BAS lodgements are due approximately 28 days after the end of each quarter, with a two-week extension available for electronic lodgements. Business owners who lodge through a registered tax agent may also be eligible for extended lodgement and payment deadlines, depending on their circumstances and compliance history.
 

What Does 'Tax Ready' Mean?

One of the most common questions from people lodging in July is why the ATO or their tax agent tells them to wait. The answer comes down to what 'tax ready' means and how the ATO's prefill system works.
 

What Is ATO Prefill Information?

ATO prefill information refers to records that are automatically loaded into a taxpayer's digital tax return using data received directly by the Australian Taxation Office (ATO) from employers, banks, health insurers, investment platforms and government agencies. This may include details such as salary and wages, bank interest, dividends and private health insurance information.

The ATO does not receive all of this data immediately after the end of the financial year. For example, employers have time after 30 June to finalise their Single Touch Payroll (STP) reporting and mark income statements as 'tax ready'. Until this process is complete, some information held by the ATO may be provisional or incomplete.

ATO prefill information is available through digital tax return platforms that support prefill services, including H&R Block's online tax platform.
 

When Is My Income Statement Tax Ready?

Most employers finalise their STP data and mark income statements as tax-ready by late July. The ATO typically has most employer data by 31 July, though some employers, particularly smaller ones or those using third-party payroll systems, may take until mid-August.

Your income statement will eventually show as either ‘Tax ready’ or ‘Not tax ready’. If you use a registered tax agent, they can usually confirm when your information has been finalised and whether it is safe to lodge.
 

Can I Lodge Before My Income Statement Is Tax Ready?

Technically yes, but the ATO specifically advises against it, and for good reason. If you lodge before your income statement is finalised and your employer subsequently changes the figures, you will need to lodge an amendment. If the ATO processes your return first and issues an assessment based on incorrect income figures, you may also attract a tax debt or an incorrect refund that the ATO will later reclaim.

For most people, the safest approach is to wait until all employer, bank, and investment information has been finalised before lodging, usually by late July or early August. H&R Block consultants check this information before your return is lodged, reducing the risk of amendments, delays, or unexpected tax debts later.
 

What Happens If I Miss the Tax Return Deadline?

Late Lodgement Penalty Explained

The FTL penalty is calculated in penalty units. For individuals and small entities, one penalty unit currently equals $364, and the ATO applies one penalty unit for each 28-day period the return is outstanding, up to a maximum of five units, which means the maximum penalty for an individual return is $1,820.

Larger entities face higher penalty amounts. The penalty clock starts from the due date, not from the date the ATO contacts you. This means penalties can accumulate before you are aware of them.
 

How to Apply for a Penalty Remission

The ATO has discretion to remit (waive) failure-to-lodge penalties where there is a reasonable explanation for the delay. Common examples include serious illness, natural disasters, family emergencies, or circumstances genuinely outside the taxpayer’s control.

In most cases, the best first step is to lodge the outstanding return as soon as possible. A registered tax agent can then request a remission on your behalf and explain the circumstances supporting the request.

Using a tax agent is often beneficial because they understand the ATO’s remission process, know what supporting information strengthens an application, and can communicate directly with the ATO on your behalf.

The ATO is generally more favourable toward taxpayers who act voluntarily and address overdue obligations promptly, particularly where there is no significant history of late lodgement.
 

Overdue and Prior-Year Returns

If you have returns outstanding from previous years, the ATO is aware of it. The ATO monitors lodgement compliance and will eventually contact individuals with outstanding returns, the timeframe varies but is rarely more than a few years before the ATO initiates contact.

In practice, taxpayers who voluntarily address overdue returns through a registered tax agent are often treated more favourably than those who wait for the ATO to initiate compliance action. Penalties are more likely to be remitted, and the ATO is more likely to accommodate a payment arrangement if tax is owed, when the taxpayer has demonstrated goodwill by voluntarily getting their affairs in order.

Business and BAS Tax Deadlines

Business owners face a more complex compliance calendar than individual taxpayers. The key deadlines for the 2025–26 financial year are as follows.

Tax agents who lodge BAS on behalf of clients receive the same extended deadline benefit as they do for income tax returns. The two-week electronic lodgement extension is also available when BAS is lodged via Standard Business Reporting (SBR)-enabled software.

Super guarantee obligations are separate from income tax and BAS deadlines and are not eligible for extension. Late super guarantee payments attract the Super Guarantee Charge (SGC), which is non-deductible and includes an administration component on top of the unpaid super itself.