BAS due dates: quarterly, monthly and through a tax agent

A quarterly BAS is due on 28 October, 28 February, 28 April and 28 July. A monthly BAS is due on the 21st of the month after the period ends. If a registered tax or BAS agent lodges for you electronically, most quarterly due dates move about four weeks later.

The dates below are for the 2026–27 financial year (1 July 2026 to 30 June 2027), from the ATO's due dates page and its BAS agent lodgment program 2026–27.

Quarterly BAS due dates (2026–27)

Most small businesses report quarterly. That applies if your GST turnover is under $20 million and the ATO has not told you to report monthly.

Quarter	Period	Standard due date	Through a registered agent
Q1	July – September 2026	28 October 2026	25 November 2026
Q2	October – December 2026	28 February 2027	28 February 2027 (no extra time)
Q3	January – March 2027	28 April 2027	26 May 2027
Q4	April – June 2027	28 July 2027	25 August 2027*

* The ATO lists 25 August 2027 for Q4 but notes it will be confirmed when it publishes the 2027–28 program.

Why Q2 has no extension. The December quarter's standard date of 28 February already includes a one-month extension for the holiday period, so the ATO does not give agents any further time on it.

Lodging online yourself. The ATO says you may get an extra two weeks on a quarterly BAS if you lodge online – again, except for Q2. The longer agent dates are only for statements lodged by a registered agent.

Monthly BAS due dates

You report monthly if your GST turnover is $20 million or more, or if the ATO has directed you to, and some smaller businesses choose to. A monthly BAS is due on the 21st day of the following month – so the July BAS is due on 21 August.

There is one exception. The December monthly BAS is normally due on 21 January, but the ATO allows eligible businesses until 21 February – those with turnover of up to $10 million who report GST monthly and lodge electronically. For 2026–27, that means the December 2026 BAS is due on 21 January 2027, or 21 February 2027 if you qualify. Businesses registered for deferred GST are not eligible.

When the agent dates apply

The later dates are not automatic just because you have an accountant. The ATO applies them when:

• the BAS is lodged electronically by a registered tax or BAS agent, and
• your previous activity statement was also lodged electronically.

If it is your first BAS, or your last one was lodged on paper, an earlier due date may apply. Always check the due date shown for your account.

Weekends, public holidays and nil BAS

• If a due date falls on a weekend or public holiday, you can lodge and pay on the next working day.
• If you had no sales or purchases in the period, you still need to lodge a nil BAS by the due date.

Common questions

When is my quarterly BAS due?

28 October (July–September), 28 February (October–December), 28 April (January–March) and 28 July (April–June). Through a registered agent, three of those move later – to 25 November, 26 May and 25 August for 2026–27.

Does paying late cost me anything?

Unpaid amounts attract the general interest charge from the due date, and a late lodgement can attract a failure to lodge penalty. If you cannot pay in full, lodge on time anyway and talk to the ATO about a payment plan.

Do I need to lodge a BAS if I'm not registered for GST?

Possibly. A BAS also reports PAYG withholding for employees and PAYG instalments, so you may still receive one. If you are unsure, ask us.

When must I register for GST in the first place?

Generally once your GST turnover reaches $75,000. See our guide to the GST registration threshold.

How we can help

We prepare and lodge BAS as a registered tax agent, so eligible clients get the later lodgment program dates. See our GST and BAS service and bookkeeping, send us a question or call (02) 9386 0500.