To help our clients plan ahead and stay compliant, we’ve prepared a 2026 BAS Due Dates guide for clients whose BAS is prepared and lodged by STA Accountants. The guide outlines key reconciliation, lodgement, and payment dates for the 2026 calendar year, along with what we need from you each BAS period to ensure your BAS is prepared accurately and lodged on time.

It’s important that your accounting records are reconciled — or source information provided — by the dates listed. Delays in providing information can place pressure on lodgement timeframes and may result in ATO late-lodgement penalties. This guide applies only to BASs lodged by STA on your behalf; if you lodge your own BAS, earlier ATO due dates may apply.

👉 BAS Preparation and Lodgements Dates

If you have any questions or are unsure what applies to your business, please contact your usual STA team member.