The ATO's maintenance calendar matters for anyone who left their tax bill until the last minute. The tax office has scheduled major system maintenance across four November weekends, and one window starts on the evening of 21 November, the date the ATO lists for self-preparers' tax bills. With the ATO also due to stop accepting Credit cards after 30 November, the timing of these outages matters more than usual this month.

The four November windows

The ATO's system maintenance page lists four scheduled windows for November 2026. All times are Australian Eastern Daylight Time.

  • Saturday 7 November, 10:00pm, to Sunday 8 November, noon: monthly maintenance.
  • Friday 13 November, 11:30pm, to Monday 16 November, 7:00am: an integrated release.
  • Saturday 21 November, 10:00pm, to Monday 23 November, 7:00am.
  • Friday 27 November, 11:30pm, to Monday 30 November, 7:00am.

Two of the windows cover almost an entire weekend, running from late Friday night until early Monday morning.

The ATO also notes that times can extend by up to three hours, so a window scheduled to end at 7am could run until 10am.

On top of the four major windows, the ATO runs routine weekly maintenance. According to its maintenance page, this happens:

  • Tuesday 11:30pm to Wednesday 7:00am.
  • Thursday 11:30pm to Friday 7:00am.
  • Saturday 11:30pm to Sunday 7:00am.

These times are also AEDT and can also run longer than scheduled.

What could be affected

According to the ATO, the systems that "may be impacted in part or in full" include:

  • ATO Online Services for Individuals and for sole traders.
  • Some features of the ATO app.
  • Online services for agents and for business.
  • The online TFN application.
  • Single Touch Payroll and Standard Business Reporting.

The wording "in part or in full" means not every service will necessarily be down for the whole window. But people planning to log in to check a balance, set up a payment or update details may not be able to.

The ATO's list does not set out every payment channel.

The list also shows the outages reach beyond individual taxpayers. Employers report pay events through Single Touch Payroll, and many businesses lodge through software that uses Standard Business Reporting. Businesses that run payroll or lodge on weekends may be affected by the windows, and tax agents' online services can also be affected. Someone applying online for a tax file number, such as a first-time worker, may also face a delay.

The tax bill due date clash

The ATO's "final countdown" release of 19 October says tax bills for self-preparers are due on 21 November.

This year, 21 November 2026 falls on a Saturday, and the third maintenance window starts at 10pm that night.

The ATO lists 21 November as the due date. The notice of assessment and the ATO's guidance on payment timing set out when a payment is due and how it will be treated.

The notice of assessment shows the amount and due date, and the maintenance windows are listed above.

On the published schedule, the major window on 21 November does not begin until 10pm. Daytime on the due date itself sits outside it, though leaving payment that late still carries risk if anything else goes wrong.

The ATO's final countdown release also makes a related point: lodging late does not change when the tax bill is due.

Hypothetical example: how much time is offline

Hypothetical example: Consider how the scheduled windows add up across the month.

The 7–8 November window runs from 10pm to noon the next day, a total of 14 hours. The 13–16 November window runs from 11:30pm Friday to 7am Monday, a total of 55.5 hours.

The 21–23 November window runs from 10pm Saturday to 7am Monday, a total of 33 hours. The 27–30 November window is another 55.5 hours.

Together, the four scheduled windows total 158 hours. If each one ran the maximum three hours over, that would add 12 hours, taking the possible total to 170 hours.

Now picture a self-preparer, Kim, who plans to log in at 10:30pm on Saturday 21 November to arrange a payment. On the published schedule, the window would already have started half an hour earlier, and it is not due to end until 7am on Monday 23 November.

The example uses only the scheduled windows. It does not include the weekly maintenance described above, and real disruption may be shorter if only some systems are affected.

Credit cards, the refresh and other context

The final window, from late Friday 27 November to Monday 30 November, falls on the last weekend before the ATO stops accepting credit card payments. A release on the ATO's media centre confirms it will stop accepting credit cards after 30 November 2026.

Separately, the ATO has begun a design and navigation refresh of its online services from November 2026 for individuals, agents and businesses, with the ATO app to follow from early 2027. The ATO describes it as "a design and navigation refresh only". Even so, some screens may look different when you next log in.

Key dates to watch

  • Saturday 7 November, 10pm, to Sunday 8 November, noon: monthly maintenance.
  • Friday 13 November, 11:30pm, to Monday 16 November, 7am: integrated release.
  • Saturday 21 November: the date the ATO lists for self-preparers' tax bills. Maintenance starts at 10pm and runs until 7am on Monday 23 November.
  • Friday 27 November, 11:30pm, to Monday 30 November, 7am: the final November window.
  • 30 November: the last day the ATO accepts credit card payments.

The ATO can change its maintenance schedule, so the system maintenance page is the most current source for these times.