BAS Due Dates 2026: Quarterly and Monthly Lodgement Calendar for Australia
Missing a BAS deadline triggers ATO penalties that compound every 28 days. This is your complete 2026 BAS due date calendar for all Australian business types โ quarterly, monthly, and annual reporters.
2026 Quarterly BAS Due Dates
Most Australian businesses lodge their BAS quarterly. Here are the 2026 due dates:
| Quarter | Period Covered | Due Date (Standard) | Tax Agent Due Date |
|---|---|---|---|
| Q1 2025-26 | 1 Jul โ 30 Sep 2025 | 28 October 2025 | 25 November 2025 |
| Q2 2025-26 | 1 Oct โ 31 Dec 2025 | 28 February 2026 | 28 February 2026 |
| Q3 2025-26 | 1 Jan โ 31 Mar 2026 | 28 April 2026 | 25 May 2026 |
| Q4 2025-26 | 1 Apr โ 30 Jun 2026 | 28 July 2026 | 25 August 2026 |
Monthly BAS Lodgement
If your business GST turnover exceeds $20 million, you must lodge and pay your BAS monthly. Monthly BAS is due on the 21st of the following month:
| Month | Due Date |
|---|---|
| January 2026 | 21 February 2026 |
| February 2026 | 21 March 2026 |
| March 2026 | 21 April 2026 |
| April 2026 | 21 May 2026 |
| May 2026 | 22 June 2026 |
| June 2026 | 21 July 2026 |
| July 2026 | 21 August 2026 |
| August 2026 | 21 September 2026 |
| September 2026 | 21 October 2026 |
| October 2026 | 21 November 2026 |
| November 2026 | 21 December 2026 |
| December 2026 | 21 January 2027 |
Annual GST Reporters
If your GST turnover is under $75,000 and you've chosen to register voluntarily, you may be eligible to lodge your BAS annually. Annual BAS is due on 31 October following the end of the financial year (i.e., 31 October 2026 for the 2025-26 financial year).
Tax Agent Extension Dates
Registered BAS agents and tax agents can lodge on behalf of clients and qualify for extended deadlines. Using a registered agent is one of the easiest ways to get more time to prepare your BAS without incurring penalties.
Penalties for Late BAS Lodgement
Setting Up BAS Reminders
- Set a calendar reminder 4 weeks before each BAS due date to start gathering records
- Set a second reminder 1 week before to review and prepare the BAS
- Enable the ATO's email or SMS reminder service through your myGov account
- Use accounting software (Xero, MYOB, QuickBooks) to auto-generate BAS reports
- Consider engaging a registered BAS agent for both time savings and extended deadlines
Mark all four quarterly BAS due dates in your calendar now: 28 October, 28 February, 28 April, and 28 July. Set reminders 4 weeks before each date. Using a registered BAS agent gives you extended deadlines and professional accuracy โ well worth it for most small businesses.