Australian dates for your diary: September 2026

The dates below are the ones left in September 2026 and the ones behind them in October. Most apply to any business with employees or a GST registration. The trust account items apply to law practices only, and say so.

Still to come in September

• Monday 21 September: the August monthly activity statement, if you report GST or PAYG withholding monthly. For law practices, the August trust account reconciliation is due the same day.
• Wednesday 30 September: the September quarter ends. It is also the last day for the Single Touch Payroll finalisation declaration for closely held payees. That applies where you have both closely held payees and arm's length employees.

October

• Wednesday 7 October: the September payroll tax return and payment, if your wages are over your state's threshold. New South Wales, Victoria and Queensland all give you 7 days after the end of the mont
• Wednesday 21 October: the September monthly activity statement, and payment of the annual PAYG instalment notice.
• Wednesday 28 October: the July to September BAS, and the quarter's PAYG instalment. A registered BAS or tax agent lodging electronically has until 25 November. If you lodge your own quarterly BAS onli
• Monday 2 November: individual, partnership and trust income tax returns, and the annual GST return. The date is 31 October, which falls on a Saturday, and the ATO's rule is that a due date on a weeken

No quarterly super guarantee date falls in October. Payday super replaced it on 1 July, which is the first of the two changes below.

Payday super, since 1 July

Super now has to reach each employee's fund within 7 business days of payday, with enough information for the fund to allocate it. The quarterly deadline is gone for anything paid from 1 July 2026, though the old rules still govern earnings paid up to 30 June. It was made law by the Treasury Laws Amendment (Payday Superannuation) Act 2025 and the Superannuation Guarantee Charge Amendment Act 2025.

Two things inside that rule regularly catch people. A new employee, and some other cases, get 20 business days rather than 7. And a business day here excludes any day that is a public holiday for a whole state or territory, anywhere in Australia. Your own location makes no difference. Monday 5 October is a public holiday in New South Wales, Queensland, South Australia and the ACT. So it is not a business day for payday super in Melbourne or Perth either.

AML/CTF, since 1 July

The AML/CTF reforms began on 1 July 2026. AUSTRAC says they may apply to a business providing designated services. A legal professional, an accountant, a conveyancer, a real estate professional, or a dealer in precious metals, stones or related products. What decides it is whether you provide a designated service, not what licence or practising certificate you hold.

A business that was providing one on 1 July had to enrol with AUSTRAC by 29 July 2026. That date is not a gate that has closed. The rule underneath it asks you to enrol no later than 28 days after you start providing a designated service. If you should have enrolled and have not, enrol, then build the program and the customer checks.

Law practices: the monthly trust reconciliation

In New South Wales and Victoria the deadline comes from rule 48 of the Legal Profession Uniform General Rules 2015, headed "Reconciliation of trust records". Rule 48(3) and (4) say:

The statements must be prepared within 15 working days after the end of the month concerned. (4) The statements must be kept by the law practice.

That is the whole requirement in those two states. The Uniform Rules do not ask a principal to review or sign the reconciliation. A practice that believes they do is holding itself to a Queensland rule.

Queensland's equivalent is section 44 of the Legal Profession Regulation 2017, and it does ask for a review. Section 44(3) says the statements must be:

(a) prepared within 15 working days after the end of the month concerned; and (b) reviewed by a principal of the law practice; and (c) annotated in a way that evidences the completion of the review; and (d) kept by the law practice.

Note the words: reviewed and annotated, not signed. The annotation on the reconciliation is what evidences the review, so the rule never asks for a separate signed cover sheet.

September's reconciliation is 15 working days after 30 September, and that lands differently across the states this year. Monday 5 October is Labour Day in New South Wales and the King's Birthday in Queensland. Counting weekdays and skipping those holidays gives Wednesday 21 October in Victoria, and Thursday 22 October in New South Wales and Queensland. Neither instrument defines "working day". Those are the ordinary reading rather than a date either regulator publishes, and the earlier one is safer where you are unsure.

Putting them somewhere you will see them

A date in a newsletter is a date nobody sees again. Whatever you run your business in, the ones above are worth entering once as recurring tasks, each naming the person who does it. The monthly activity statement, the payroll tax return, the quarter's BAS, and for a practice, the reconciliation. The point is that the reminder arrives without anybody remembering to send it.

This article is general information about Australian filing dates and rules. It is not legal, tax or accounting advice, and it does not take account of your circumstances. It is current as at 21 September 2026. These dates come from the ATO's due dates pages, Revenue NSW and the Victorian State Revenue Office. Also the Queensland Revenue Office, AUSTRAC and the Fair Work Ombudsman's public holiday list. The rules quoted are the Legal Profession Uniform General Rules 2015 (NSW) as in force on that date. Also the Legal Profession Regulation 2017 (Qld) as in force from 1 March 2024. Check your own regulator for anything specific to you.