Australia / Guides / BAS deadlines: the quarterly rhythm, plainly
Australia · guideBAS deadlines: the quarterly rhythm, plainly
The short answer
A quarterly Business Activity Statement is due on the 28th of the month following the end of the quarter, except the December quarter, which is due 28 February — an extra four weeks built into the standard calendar. A business lodging through a registered tax or BAS agent may get a further concessional date on top of that, but the concession belongs to the agent's lodgment program, not to the business, and it does not apply to every quarter. Monthly lodgers work to a separate, tighter cycle: the 21st of the following month, every month.
Key facts — verified dates on each
The four quarters and their standard due dates
The Australian financial year splits into four BAS quarters, each with its own standard due date set by the ATO: the July–September quarter is due 28 October, the October–December quarter is due 28 February, the January–March quarter is due 28 April, and the April–June quarter is due 28 July.
Three of the four dates fall exactly one month after the quarter ends. The October–December quarter is the exception — its due date is 28 February, two months out rather than one, because it spans the end-of-calendar-year period. That built-in gap is a feature of the standard calendar, not a concession anyone has to apply for.
When any of these dates lands on a weekend or public holiday, it moves to the next business day. The current-year dates are worth checking directly on the ATO's BAS due-dates page each quarter rather than carried forward from a prior year's calendar, since a shifted weekday can move the practical deadline by a day or two.
Monthly BAS runs on a different, tighter cycle
Some businesses lodge monthly instead of quarterly — mandatory once GST turnover reaches $20 million, and optional below that for businesses that prefer smaller, more frequent payments. Monthly BAS is due on the 21st of the month following the reporting month: a July BAS is due 21 August, an August BAS is due 21 September, and so on, twelve times a year rather than four.
The two cycles do not mix within one BAS period. A business reporting monthly is never working toward one of the four quarterly dates above — it is on its own calendar, and the reconciliation work that feeds each BAS has to be current every month rather than banked up for a quarter.
The lodgment-program concession: whose extension it is
A business that lodges its BAS electronically through a registered tax or BAS agent can, for some quarters, get a later due date than the standard one above. This is the ATO's lodgment program for agents — a concession built around the agent's registration and their electronic-lodgment track record with the ATO, not a general extension available to every business that asks.
The concession is not uniform across the year. It typically applies to the July–September, January–March, and April–June quarters, pushing each of those out by several weeks. The October–December quarter — already extended to 28 February under the standard calendar — usually gets no further concession on top of that, because the standard date already sits two months after quarter-end.
Because the concession depends on the specific agent's lodgment program and can shift from one program year to the next, a business that lodges through an agent gets its concessional date from that agent rather than assuming a specific week. The mechanism is public on the ATO's BAS agent lodgment program page; the actual date for a given quarter is a conversation with whoever lodges the statement.
What has to be reconciled before a BAS is ready
A BAS is only as accurate as the ledger behind it. Before the quarter (or month) closes, the transactions for the period need to be coded to the right GST treatment — taxable, GST-free, input-taxed, or out of scope — bank and card accounts need to be reconciled to the general ledger, and sales and purchase invoices need to match what actually settled, not just what was issued.
Payroll sits alongside this on its own track. Single Touch Payroll reporting to the ATO is a function of whoever runs payroll for the business — typically the registered agent handling pay runs — and STP reporting obligations are separate from the BAS itself, even though both draw on the same underlying payroll records.
Superannuation guarantee is similar: whether super has been correctly calculated and paid for a quarter is a liability question that sits with the business's registered agent or adviser, not something a BAS reconciliation resolves on its own. A bookkeeping function keeps the ledger clean enough for that liability to be assessed accurately, but does not assess it.
Where CapEasy's work fits, and where it stops
Licensed BAS and tax work runs through the business's registered BAS or tax agent. Our bookkeeping work for Australian clients keeps the ledger current — transactions categorised, accounts reconciled, GST coding consistent quarter to quarter — so that whoever prepares and lodges the BAS is working from clean books rather than reconstructing a quarter from scratch under deadline pressure.
Ascertaining or advising on a BAS or tax position, preparing or lodging a BAS, dealing with the ATO on a client's behalf, and determining a superannuation guarantee liability are functions carried out by the business's registered BAS or tax agent, who is the one positioned to claim any lodgment-program concession and to sign what gets submitted.
The figures, and when we checked them
These numbers change by year or by notification. Each one shows the date we last verified it against the source — if that date looks old, check the source before relying on it.
Questions on this
What are the four quarterly BAS due dates?
28 October for July–September, 28 February for October–December, 28 April for January–March, and 28 July for April–June. The date moves to the next business day if it falls on a weekend or public holiday.
Why is the October–December quarter due two months later instead of one?
The standard ATO calendar builds in an extra four weeks for that quarter, landing its due date on 28 February rather than 28 January. It spans the holiday period, and the later date is part of the standard schedule, not something applied for.
How does monthly BAS lodgment differ from quarterly?
Monthly BAS is due on the 21st of the following month, every month, rather than four times a year. Reporting monthly is mandatory once GST turnover reaches $20 million and optional below that threshold.
What is the registered-agent lodgment-program concession?
It is an ATO program that gives some quarterly due dates a later date when a BAS is lodged electronically through a registered tax or BAS agent. The concession is tied to the agent's own lodgment-program standing, not automatically available to every business.
Does the lodgment-program concession apply to every quarter?
No. It typically extends the July–September, January–March, and April–June quarters. The October–December quarter, already extended to 28 February under the standard calendar, usually receives no further extension.
Who decides whether a business gets the concessional date?
The registered tax or BAS agent lodging the statement. Eligibility depends on that agent's electronic-lodgment track record with the ATO, so the specific date for a given business comes from the agent, not from a general public schedule.
What needs to be done to the books before a BAS can be prepared?
Transactions for the period coded to the correct GST treatment, bank and card accounts reconciled to the general ledger, and sales and purchase records matched to what actually settled. A BAS prepared from unreconciled books carries that inaccuracy straight through.
Is Single Touch Payroll reporting part of the BAS?
No, though both draw on the same payroll records. STP reporting to the ATO is a function of whoever runs payroll for the business, typically the registered agent, and is tracked separately from the BAS lodgment cycle.
Does reconciling the books resolve superannuation guarantee liability?
No. Clean books support that assessment, but whether super guarantee has been correctly calculated and paid for a quarter is a liability question for the business's registered agent or adviser to determine, not something bookkeeping reconciliation resolves on its own.
Does CapEasy lodge BAS or deal with the ATO for a client?
Licensed BAS and tax work runs through the business's registered BAS or tax agent. Our bookkeeping work keeps the ledger reconciled and GST-coded so a registered agent can prepare and lodge the BAS; ascertaining or advising on a BAS position, lodging it, and communicating with the ATO on a client's behalf are handled by that registered agent.
Primary sources
- ATO — Due dates for lodging and paying your BAS
- ATO — BAS agent lodgment program 2026–27
- ATO — Activity statements (due dates by topic)
- ATO — Monthly GST reporting
Last reviewed 2026-08-14. Statutes and schedules change — the sources above are authoritative, this page is orientation.
Related
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