BAS Due Dates 2026-27: Every Deadline Australian SMEs Need to Know

Your BAS due date depends on three things: how often you report (quarterly or monthly), whether you lodge yourself or through a registered tax or BAS agent, and whether the date lands on a weekend or public holiday. Below are the FY2026-27 dates as the ATO publishes them, with the conditions attached to each. Every date is taken from the ATO pages linked at the end of this article, as read on 15 July 2026, and the same verified data sits behind our FY2026-27 ATO key dates reference.

Quarterly BAS due dates for FY2026-27

Quarterly is the standard cycle if your GST turnover is under $20 million and the ATO hasn't directed you to report monthly. The ATO's rule is that a quarterly activity statement is due on the 28th day of the month after the quarter ends, except quarter 2, which is due 28 February because that date already includes a one-month extension.

*28 February 2027 falls on a Sunday. The ATO's rule is that if a due date falls on a weekend or public holiday you have until the next business day to lodge and pay, which would make the effective day Monday 1 March 2027. The ATO's pages still print 28 February 2027, so treat 1 March as the rule applied rather than an ATO-printed date. The other three quarterly dates fall on weekdays.

One more quarter falls inside this financial year: the final quarter of FY2025-26 (April–June 2026) is due 28 July 2026, or 25 August 2026 under the agent lodgment program.

Lodging yourself vs lodging through an agent

Lodging yourself on the standard timeline: the standard dates in the table apply.

Lodging yourself online: the ATO says you may be eligible for an extra two weeks to lodge and pay quarters 1, 3 and 4 — it isn't automatic. Its due-dates-by-month calendar publishes those later dates as 11 November (quarter 1), 12 May (quarter 3) and 11 August (quarter 4), as day-and-month entries rather than year-stamped FY2026-27 dates. There is no later date for quarter 2.

Lodging through a registered tax or BAS agent: when your agent lodges electronically through Online services for agents or the Practitioner lodgment service (PLS), the lodgment program dates in the right-hand column apply. They come with conditions. A program date applies only to an eligible activity statement that generates after your previous one was lodged electronically, so your first activity statement, or one that follows a paper-lodged statement, may carry an earlier date. Statements that include a monthly PAYG instalment obligation, PAYG instalment statements for consolidated head entities, monthly GST cycles (apart from the December concession below) and quarterly instalment notices (forms R, S and T) are excluded from the concession.

Monthly BAS and instalment activity statements

Monthly GST reporting is mandatory once GST turnover reaches $20 million (and must be lodged online). Smaller businesses can choose it, and the ATO can direct a business to report monthly if it hasn't been meeting its GST obligations. Monthly activity statements for PAYG withholding and PAYG instalments follow the same rule.

The rule is simpler than the quarterly one: lodge and pay by the 21st day of the month after the period ends — the ATO's own example is that a July monthly BAS is due 21 August. No electronic or agent lodgment concession applies to standard monthly statements.

There is one exception. The December monthly statement, with a standard due date of 21 January, is due 21 February for agent-lodged business clients with up to $10 million annual turnover who report GST monthly and lodge electronically. Businesses registered for deferred GST aren't eligible for the later date, and schools and associated bodies have needed to lodge their December BAS by 21 January since December 2024.

PAYG instalments that arrive with the BAS

If you pay PAYG instalments quarterly, the due dates line up with the quarterly BAS: 28 October 2026, 28 February 2027, 28 April 2027 and 28 July 2027 (the ATO year-stamps these for quarterly instalment notices, forms R, S and T). Two things differ from the BAS itself. If you receive an instalment notice and pay the amount shown, you don't need to lodge the notice, just pay by the due date — and instalment notices aren't eligible for agent lodgment program dates. If you receive an activity statement and lodge online you may be eligible to lodge and pay two weeks later, but if you pay GST monthly your due date is the 21st of each month and the two-week extension isn't available.

Annual GST reporting

Businesses that report GST annually — voluntary registrants with GST turnover under $75,000, or $150,000 for not-for-profit bodies — lodge an annual GST return by 31 October with the income tax return, or by 28 February following the annual tax period if no tax return is required. Through a registered agent, the due date is your tax return due date, or 28 February 2027 where there is no return to lodge.

Paying is a separate obligation from lodging

Lodging and paying usually share a date, but they are separate obligations, and interest can apply to amounts paid late even where the statement was lodged on time. If cash flow is tight, lodge on time regardless — lodging late has its own consequences — and talk to the ATO or your agent about a payment arrangement rather than going quiet.

Build a system so the dates never sneak up

The businesses that don't miss a BAS treat it as a rhythm rather than an event. A few habits that work:

• Reconcile your accounts as you go, so preparing the BAS is a review rather than a scramble.
• Diarise your own internal deadline a week or two before the real one, as a recurring task rather than something you remember.
• Set GST and PAYG aside as they are collected — ideally in a separate account — so the money is there when the payment falls due.
• If you use an agent, keep lodging electronically through them every quarter: the program dates only apply to statements that generate after your previous one was lodged electronically.

Getting this right is core to your finance function and to a back office where the numbers you report are already reconciled rather than assembled at the last minute. That is the work behind our BAS and tax compliance service, and the full calendar — BAS, PAYG instalments, payday super, TPAR and FBT — is on the FY2026-27 ATO key dates page.

Sources and a caveat

The dates above come from the ATO's due dates for lodging and paying your BAS page, its BAS agent lodgment program 2026-27 and the registered agent lodgment program dates for activity statements, as read on 15 July 2026. Only the agent lodgment program pages year-stamp FY2026-27 dates; the general business pages publish day-and-month rules. The ATO can grant deferrals to specific taxpayers (natural disaster relief, for example), the agent program dates are conditional, and the quarter 4 2026-27 agent date is provisional until the 2027-28 program is published. Confirm your own dates against your activity statement, your agent or the ATO before relying on them. This is general information, not tax advice for your circumstances.