Upcoming ATO Deadlines
The table below shows all major ATO deadlines with live countdowns. Dates that have passed are marked as complete.
| Deadline | Due Date | Countdown |
|---|
Published: March 2026 | Last Updated: March 2026
Every key ATO deadline for the 2025-26 and 2026-27 financial years. Live countdowns so you never miss a lodgement date.
The table below shows all major ATO deadlines with live countdowns. Dates that have passed are marked as complete.
| Deadline | Due Date | Countdown |
|---|
If you report and pay GST quarterly, these are your lodgement deadlines for the 2025-26 financial year:
Due: 28 October 2025
Tax agent extension: 25 November 2025
Due: 28 February 2026
No tax agent extension for Q2
Due: 28 April 2026
Tax agent extension: 26 May 2026
Due: 28 July 2026
Tax agent extension: 25 August 2026
Employers must pay super guarantee contributions within 28 days of the end of each quarter. Late payments trigger the super guarantee charge (SGC), which includes the shortfall, interest of 10% per annum, and an administration fee of $20 per employee per quarter.
| Quarter | Period | Due Date |
|---|---|---|
| Q1 | 1 Jul – 30 Sep | 28 October |
| Q2 | 1 Oct – 31 Dec | 28 January |
| Q3 | 1 Jan – 31 Mar | 28 April |
| Q4 | 1 Apr – 30 Jun | 28 July |
The ATO takes late lodgement seriously. Here's what you're looking at if you miss a deadline:
| Days Overdue | Penalty Units | Amount (2026) |
|---|---|---|
| 1 – 28 days | 1 unit | $313 |
| 29 – 56 days | 2 units | $626 |
| 57 – 84 days | 3 units | $939 |
| 85 – 112 days | 4 units | $1,252 |
| 113+ days | 5 units (max) | $1,565 |
These penalties apply per statement. If you have multiple overdue BAS or tax returns, penalties accumulate across each one.
Calculate any date easily — add or subtract days, track visas, payment terms, pregnancy milestones, and more.
Open Date CalculatorWhen is the 2025-26 tax return due?
If you lodge your own return, it's due by 31 October 2026. If you use a registered tax agent, you typically have until 15 May 2027 — but you must be registered with your agent before 31 October 2026.
What are the quarterly BAS due dates for 2026?
For the 2025-26 financial year: Q1 (Jul-Sep) is due 28 October 2025, Q2 (Oct-Dec) is due 28 February 2026, Q3 (Jan-Mar) is due 28 April 2026, and Q4 (Apr-Jun) is due 28 July 2026.
What happens if I miss a BAS deadline?
The ATO may impose a failure-to-lodge penalty of one penalty unit ($313 as of 2026) for each 28-day period your BAS is overdue, up to a maximum of five penalty units ($1,565). Interest charges may also apply to any unpaid amounts.
When are superannuation guarantee payments due?
Super guarantee contributions are due 28 days after the end of each quarter: 28 October, 28 January, 28 April, and 28 July. Late payments incur the super guarantee charge (SGC), which includes interest and administration fees.
Does a weekend or public holiday extend ATO deadlines?
If an ATO due date falls on a weekend or national public holiday, the deadline is automatically extended to the next business day. Note: state-specific public holidays do not always extend ATO deadlines.