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ATO Tax Return and BAS Due Dates

Review ATO individual tax return dates, tax agent timing, payment due dates, BAS monthly and quarterly deadlines, and record workflow.

Published: May 18, 2026Updated: May 19, 2026

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ATO Deadlines Depend on Lodgment Channel and BAS Cycle

If you lodge your own Australian individual tax return, ATO guidance says the due date is generally 31 October each year. If 31 October falls on a weekend, the due date moves to the next business day.

BAS dates depend on whether the reporting period is monthly, quarterly, or annual. ATO due dates, myGov, Online services, and agent schedules should be checked before relying on a generic calendar.

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ATO Individual and BAS Date Map

Area	Typical date	Planning note
Self-lodged individual return	31 October	Next business day if the date falls on a weekend.
Tax agent returns	Agent schedule	Usually requires being on the agent list before 31 October.
Self-lodger payment	Often 21 November unless assessment timing changes.	Check the notice of assessment.
Monthly BAS	21st day after period end	Monthly GST reporters.
Quarterly BAS	Quarterly due dates with ATO concessions in some channels.	Check ATO or BAS agent schedule.

BAS Workflow for GST-Registered Businesses

Confirm whether your GST reporting cycle is monthly, quarterly, or annual.
Reconcile sales, GST collected, purchases, and input tax credits before lodgment.
Check PAYG withholding and PAYG instalment labels if included.
Keep digital records and tax invoices that support claims.
Review ATO Online services or your BAS agent for the exact due date.
Save lodgment and payment confirmations.

Tax Agent vs Self-Lodgment Timing

Self-lodge

Earlier deadline

The 31 October date is the core self-lodgment rule for individual returns.

Tax agent

Special schedules

Agent lodgment schedules can extend dates, but only when agent-list and eligibility conditions are met.

Payment

Notice controls

Payment due dates can depend on lodgment and assessment timing, so check the ATO notice.

Official Video Check

CalculatorWallah reviewed current official ATO video sources for individual return due dates and BAS due dates. No suitable single official video was found, so this guide uses ATO written sources.

ATO Scenarios That Change Lodgment Timing

Australian due dates depend heavily on lodgment channel and taxpayer profile. A self-lodged individual return usually follows the standard individual deadline, while registered tax agents can have client-specific lodgment programs. Businesses also need to track BAS frequency, GST registration, PAYG instalments, PAYG withholding, super obligations, and any ATO notices that override the general calendar.

The practical mistake is treating the tax return date and BAS dates as one calendar. A small business can lodge an income tax return through an agent while still having monthly or quarterly BAS obligations. Likewise, a taxpayer who switches agents or lodges late in a prior year may not receive the full agent-program timing they expected.

Confirm whether the return is self-lodged or handled through a registered tax agent.
Check the ATO account and notices for taxpayer-specific due dates.
Separate income tax lodgment from BAS, GST, PAYG instalment, and PAYG withholding dates.
Make sure BAS records reconcile sales, purchases, GST collected, and GST credits.
Review prior-year lodgment history before relying on agent-program timing.
Keep payment receipts and lodgment confirmations with the tax file.

Frequently Asked Questions

ATO guidance says individuals lodging their own tax return generally need to lodge by 31 October each year, with the next business day applying if 31 October falls on a weekend.

Registered tax agents generally have special lodgment schedules, but taxpayers usually need to be on the agent list before 31 October.

ATO guidance says monthly BAS is generally due on the 21st day of the month after the taxable period.

Not always. Tax agent lodgment programs depend on registration timing, client history, and ATO conditions. Check the agent and ATO account before relying on a later date.

For many individuals who self-lodge, the due date is 31 October after the end of the income year. ATO notices can set a different date.

BAS dates relate to GST, PAYG withholding, and instalments, while the income tax return has its own lodgment and payment timing.

Quarterly BAS due dates vary by quarter and lodgment channel. Use the ATO account, BAS form, or registered agent schedule for the exact date.

PAYG instalments are advance payments toward expected income tax, often based on business or investment income. They are separate from final return lodgment.

Yes. GST-registered businesses generally need to report GST through BAS or an annual GST return, depending on their reporting cycle.

Waiting can reduce errors, but you remain responsible for checking pre-filled wages, interest, dividends, private health insurance, and deductions.

The ATO may apply failure-to-lodge penalties or interest. Lodging as soon as possible and contacting the ATO can reduce follow-up problems.

Keep income statements, bank interest, dividend records, rental records, work-related deductions, business records, BAS summaries, and payment receipts.