Below is the full set of FY2026-27 quarterly BAS dates with both lodgement routes side-by-side. Three rules govern the gap between them. The dates are pulled directly from the ATO website and cross-checked against the FY27 calendar (28 February 2027 falls on a Sunday, which moves it to the next business day for everyone).
The full FY2026-27 schedule
* The standard Q2 due date is 28 February. In FY27 that falls on a Sunday, so the ATO moves the deadline to the next business day — Monday 1 March 2027 — for everyone.
Three rules that explain the table
Rule 1 — paper lodgement = the 28th of the month after the quarter ends
Q1 ends 30 September → due 28 October. Q3 ends 31 March → due 28 April. Q4 ends 30 June → due 28 July. Q2 is the odd one out because it ends 31 December and the ATO gives an extra month of breathing room over Christmas / January, so it's due 28 February instead of 28 January.
Rule 2 — online (self-lodge) adds two weeks
If you lodge through ATO Online Services for Business, myGov, or a SBR-enabled platform under your own credentials, the deadline shifts by two weeks. Q1 paper 28 Oct → online 11 Nov. Q3 paper 28 Apr → online 12 May. Q4 paper 28 Jul → online 11 Aug. The online concession is the ATO's nudge to encourage electronic lodgement.
Rule 3 — through a registered agent = roughly four extra weeks (except Q2)
Lodge through a registered tax or BAS agent and you pick up the agent concession on top: another two weeks beyond the online date. Q1 online 11 Nov → agent 25 Nov. Q3 online 12 May → agent 26 May. Q4 online 11 Aug → agent 25 Aug.
Q2 is the exception.The Christmas / January concession that pushes everyone's Q2 to 28 February uses up the extension already — there's no separate agent concession on top. Whether you lodge yourself or through us, Q2 is due 28 February (or 1 March 2027 specifically, because the 28th is a Sunday). Plan around that.
Monthly BAS lodgers
If your turnover is $20 million or more, or you've elected monthly, the rule is simpler: the BAS for a given month is due on the 21st of the next month. There's no agent concession on monthly BAS — it's 21st whether you lodge yourself or through us. For FY27 that means:
- July 2026 BAS → due 21 August 2026 (Fri)
- August 2026 → due 21 September 2026 (Mon)
- September 2026 → due 21 October 2026 (Wed)
- … and so on across the year. Same 21st rule every month, falls back to next business day if it lands on a weekend or public holiday.
Payment is due the same day as lodgement
A common misread: people lodge on time but pay late, thinking payment runs on a separate clock. It doesn't. Whatever date appears in the table above is both your lodgement deadline and your payment deadline. Late payment attracts the General Interest Charge (GIC), which from 1 July 2025 is no longer income-tax deductible — so a missed BAS payment now costs you twice (the interest + losing the deduction you used to get for it).
Annual GST returns
Voluntary GST registrations with no agent concession lodge an annual GST return. For FY27 (1 Jul 2026 – 30 Jun 2027) that's due by the same date as your income tax return — typically 31 October 2027 if self-lodging, or as scheduled by your registered agent if you're on our lodgement program.
If you miss a date
The ATO's standard penalty is a Failure-to-Lodge (FTL) fine, calculated per 28-day block of lateness, scaled by entity size (small / medium / significant global entity). For most small businesses it's currently $313 per 28-day block, capped at 5 blocks (so $1,565 maximum per BAS). The ATO usually waives the first FTL if you've had a clean lodgement history and you ring them. We typically handle that conversation for you if it ever comes up.
Sources
Standard BAS due dates and the online lodgement concession: ATO — Due dates for lodging and paying your BAS.
Registered-agent quarterly concession dates: ATO Lodgment program — Quarterly activity statements (search "lodgment program quarterly activity statements" on ato.gov.au — the URL changes between site refreshes; the substantive concession does not).
FTL penalty schedule and current penalty unit value: ATO — Failure to lodge on time penalty.
GIC non-deductibility from 1 July 2025: Treasury Laws Amendment (Tax Incentives and Integrity) Act 2025, repealing s 25-5(1)(c) of the Income Tax Assessment Act 1997.
Need us on your BAS for FY27? See our BAS service or book a 30-minute discovery call— onboarding takes about a week, and once you're on the lodgement program the agent concession applies from your next BAS.
