BAS Due Dates 2026-27: Quarterly, Monthly and Agent Dates
In Australia, a quarterly BAS for 2026-27 is due 28 October 2026, 2 March 2027, 28 April 2027 and 28 July 2027, and a monthly BAS is due on the 21st of the following month. Lodging online adds two weeks to quarters 1, 3 and 4, and a registered agent lodging electronically can have until 25 November, 26 May and 25 August. Quarter 2 gets no extension either way.
The quarterly BAS due dates for 2026-27 fall on the 28th of the month after each quarter: 28 October, 28 April and 28 July. The October to December quarter is the exception. Its standard date, 28 February 2027, is a Sunday, and Monday 1 March is Labour Day in Western Australia. The ATO treats a public holiday in any whole state as a non-business day for every taxpayer in the country, so the December quarter BAS is due Tuesday 2 March 2027, wherever you are. Several published date lists give Monday 1 March.
Nothing extends quarter 2. Lodging online adds no two weeks to it, and agents get no later date. A business used to lodging in mid or late November carries that habit into March at its cost: the BAS is late, and so is the payment.
What a BAS is and what goes on it are in the BAS explainer. Below are the dates, and the conditions that move them.
Quarterly BAS due dates for 2026-27
If your GST turnover is under $20 million and the ATO hasn’t told you to report monthly, you lodge quarterly. Your date depends on how you lodge:
| Quarter | Period | Standard due date | Lodging online yourself | Through a registered agent |
|---|---|---|---|---|
| 1 | July to September 2026 | 28 October 2026 | 11 November 2026 | 25 November 2026 |
| 2 | October to December 2026 | 2 March 2027 | No extension | No extension |
| 3 | January to March 2027 | 28 April 2027 | 12 May 2027 | 26 May 2027 |
| 4 | April to June 2027 | 28 July 2027 | 11 August 2027 | 25 August 2027 |
Payment is due on the same day as lodgement in every column. The standard dates are on the ATO’s BAS due dates page, and the date that applies to you is printed on your statement.
Quarter 2: Tuesday 2 March 2027, with no extension
When a due date isn’t a business day, you can lodge or pay on the next one. The ATO’s table of weekend and public holiday dates defines the term:
The table’s 2027 entries list 1 March as Labour Day (WA) and give the first business day as Tuesday 2 March.
Lodging and paying by Monday 1 March is safe wherever you are. The last day is 2 March.
There is no extension on top. The 28 February date already includes a one-month extension, which is the ATO’s stated reason for leaving quarter 2 out of the online offer, and the agent program lists no quarter 2 date at all.
The extra two weeks for lodging online
If you receive and lodge your quarterly BAS online, the ATO’s two-week lodgement concession moves quarters 1, 3 and 4 back by 14 days: 11 November 2026, 12 May 2027 and 11 August 2027. You don’t apply for it. Once the statement generates, the later date shows on it.
- A quarterly BAS for quarter 1, 3 or 4
- Received and lodged online
- Applied automatically, with the new date on the statement
- Monthly statements
- Monthly GST payers who pay PAYG instalments quarterly
- Quarterly instalment notices (forms BAS R, BAS S and BAS T)
- Large business clients on substituted accounting periods
- Any statement without an original due date of the 28th
If the ATO sends you a GST or PAYG instalment notice instead of a BAS, its date stays on the 28th, even if you pay it online.
If you’re lodging through an agent
A registered tax or BAS agent lodging electronically gets four weeks rather than two on quarters 1, 3 and 4: 25 November 2026, 26 May 2027 and 25 August 2027, as set out in the ATO’s BAS agent lodgement program for 2026-27. Quarter 2 has no agent date.
The agent dates come with a condition. They apply to a statement that generates after the client’s previous statement was lodged electronically. A business’s first statement, or one following a paper lodgement, may carry the standard date. If you are moving to an agent partway through the year, ask which date your next statement carries rather than assuming the later one.
Our BAS lodgement is lodged as a registered agent, and we track the due dates for you.
Monthly BAS due dates for 2026-27
A monthly BAS is due on the 21st of the month after the period ends. Three of this year’s 21sts fall on a weekend, which moves them to the Monday after.
| Month | Due date | Note |
|---|---|---|
| July 2026 | 21 August 2026 | |
| August 2026 | 21 September 2026 | |
| September 2026 | 21 October 2026 | |
| October 2026 | 23 November 2026 | 21 November is a Saturday |
| November 2026 | 21 December 2026 | |
| December 2026 | 21 January 2027 | Later through an agent, below |
| January 2027 | 22 February 2027 | 21 February is a Sunday |
| February 2027 | 22 March 2027 | 21 March is a Sunday |
| March 2027 | 21 April 2027 | |
| April 2027 | 21 May 2027 | |
| May 2027 | 21 June 2027 | |
| June 2027 | 21 July 2027 |
Neither the online two weeks nor the agent concession applies to a standard monthly statement. Monthly reporting is compulsory once GST turnover reaches $20 million or the ATO directs it, and a choice below that.
December is the one monthly exception, and only through an agent
The December monthly statement is due 21 January 2027 if you lodge it yourself. Lodged electronically by a registered agent, for a business with turnover up to $10 million that reports GST monthly, it moves to 21 February. That is a Sunday in 2027, so the agent date is Monday 22 February 2027.
Some date lists give 22 February to every monthly lodger as a Christmas extension. Lodging yourself, December and January are due a month apart, on 21 January and 22 February.
The annual GST return
Annual reporting is only open to a business voluntarily registered for GST with GST turnover under $75,000, or $150,000 for a not-for-profit. The GST registration threshold guide covers the point where registration stops being voluntary. The annual GST return is due 31 October, or 28 February following where you don’t have to lodge a tax return. An agent may have different dates.
The annual return falling due this year covers 2025-26. Because 31 October 2026 is a Saturday, it is due Monday 2 November 2026, the same shift that applies to a self-lodged tax return. Where no tax return is required, its 28 February 2027 date moves to 2 March 2027 for the same reason as quarter 2. The 2026-27 annual return is due 31 October 2027, which is a Sunday, so the next business day.
Paying, and what a missed date costs
Lodging and paying share one date, and the payment due date is printed on the statement. You can pay early against a future BAS if that suits your cash flow.
Lodge late and the ATO warns you before applying a failure to lodge penalty. The penalty is one penalty unit, $364 from 1 July 2026, for each 28 days or part of 28 days the BAS is late, capped at five units, or $1,820, for individuals and small withholders (businesses withholding less than $25,000 a year). A late statement that comes out at a refund or nil generally attracts no penalty, unless one was applied before you lodged it.
Pay late and general interest charge accrues on the unpaid amount, worked out daily and compounding. GIC charged from 1 July 2025 isn’t tax deductible.
If you can’t pay, lodge on time anyway and contact the ATO before the due date. If you owe $200,000 or less, you may be able to set up a payment plan yourself through ATO online services, and every plan starts with an up-front payment.
Changing how often you lodge
Below $20 million GST turnover you can switch between quarterly and monthly. Ask early in a lodgement period and the new cycle can generally start straight away. Ask later and it starts from the next quarter or year. A second change within 12 months may be refused. Sole traders phone the ATO or apply in writing, and other businesses can request it through Online services for business.
For most quarterly lodgers, the first date of the year is 28 October 2026.
Quick answers
When is the December quarter BAS due in 2027?
Tuesday 2 March 2027. The standard date, 28 February, is a Sunday, and Monday 1 March is Labour Day in Western Australia. The ATO counts a public holiday in any whole state as a non-business day for everyone, so every business in Australia has until 2 March, and there is no online or agent extension on top.
Do I get an extra two weeks if I lodge my BAS online?
For quarters 1, 3 and 4, if you receive and lodge the statement online, and the later date appears on the statement automatically. It does not apply to quarter 2, to monthly statements, or to quarterly instalment notices, so a sole trader paying from a GST or PAYG instalment notice keeps the 28th.
What are the BAS agent due dates for 2026-27?
25 November 2026 for quarter 1, 26 May 2027 for quarter 3 and 25 August 2027 for quarter 4, where the agent lodges electronically. Quarter 2 has no agent date. The later dates apply to a statement that generates after your previous one was lodged electronically, so a first statement, or one following a paper lodgement, may carry the earlier date.
When is the December monthly BAS due?
21 January 2027 if you lodge it yourself. Through a registered agent lodging electronically, for a business with turnover up to $10 million, it moves to 21 February, which is a Sunday in 2027, so Monday 22 February 2027. It is the only monthly statement with a concession.
What happens if I lodge my BAS late?
The ATO warns you before applying a failure to lodge penalty. The penalty is one penalty unit, $364 from 1 July 2026, for each 28 days or part of 28 days late, up to five units for individuals and small withholders. Unpaid amounts also attract general interest charge, worked out daily and compounding.