September 2026 Tax Calendar Australia
The standalone calendar app is now the primary experience. This main-site monthly view remains available as a fallback during the transition.
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Key dates in September 2026
30 September 2026
STP finalisation due for closely held payees
Finalisation due date for closely held payees where this rule applies.
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FAQ
What is the self-lodgment deadline?
For most individuals, the self-lodgment deadline is 31 October each year, with next business day treatment if needed.
Are these dates legal advice?
No. This calendar is informational only. Always confirm your exact obligation on the ATO website or with a registered tax agent.