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Key Dates – September 2026

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Key business lodgement dates for September 2026 including BAS and PAYG deadlines, Optima Partners

Staying on top of your compliance deadlines keeps your business running smoothly and avoids unnecessary penalties. Here are the key dates business owners need on their calendar for September 2026.

21 September

Lodge and pay your August 2026 monthly Business Activity Statement (BAS).

If you report GST monthly, this is your deadline to lodge and pay for the August period.

30 September

Lodge your PAYG Withholding Payment Summary Annual Report. This applies if it was prepared by a BAS agent or tax agent, and excludes large withholders whose annual withholding exceeds $1 million.

Lodge your Annual TFN Withholding Report 2026. This applies if you’re the trustee of a closely held trust that was required to withhold amounts from payments to beneficiaries.

Staying Ahead of Deadlines

Missing a lodgement date can lead to penalties and unwanted attention from the ATO, as well as the administrative headache of catching up. Building a simple compliance calendar, or having your advisory team manage it for you, takes this off your plate entirely.

Here at Optima Partners, our Business Advisory team keeps clients ahead of these dates as part of our ongoing service, ensuring nothing slips through the cracks.

If you’d like help staying on top of your compliance calendar, get in touch with us here.

Optima Partners offers support to all businesses. Whatever your requirements

For more information on how Optima Partners’ services can help your business, contact the team at info@optimapartners.com.au for a consultation.

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