Key Highlights

  • Calendar-year multinationals have until 29 January 2027 to lodge their first public tax reports.
  • Registration is required four weeks before the report deadline.
  • Reports are given to the ATO in an approved form and then published on the government open data site.
  • Late publication may attract penalties, according to the ATO.

Australia's push to make big multinationals publish where they earn profits and pay tax is reaching its first major deadline. Groups with calendar-year reporting periods face a 31 December 2026 due date for their first public country-by-country reports. But the ATO has confirmed an automatic deferral that gives them until 29 January 2027. That pushes much of the first wave of public data on some of the world's largest companies into the new year.

The new deferral in the ATO's words

Under the ATO's guidance, a group must publish its public country-by-country (CBC) report "by giving the information to us in the approved form within 12 months following the end of your reporting period."

For groups with a reporting period from 1 January 2025 to 31 December 2025, that would mean a due date of 31 December 2026. The ATO now says: "You now have until 29 January 2027 to publish the report, but are encouraged to send it in earlier if it is ready."

The deferral is automatic, so eligible groups do not need to apply for it. The ATO page setting it out was updated on 27 October 2026. Groups needing more time beyond that can request an extension by email, the ATO says.

What 'publishing' actually means

Under the Australian system, a multinational does not post the report on its own website to meet the rule. It gives the information to the ATO in an approved form, and the ATO passes it to data.gov.au, the Australian Government's open data website.

The ATO has said "It is expected that the first Public CBC reports will be made available on data.gov.au" in late 2026. With the deferral, reports from calendar-year groups may reach the site only after the ATO receives them in January and completes its checks.

Before publication, the ATO checks each report for validation issues and may contact the group to resolve them. The ATO stresses that validation does not confirm a report is complete or accurate. The group remains responsible for its content. If a group later finds a material error after publication, it must amend and republish the report.

What will be published

The regime passed Parliament without amendment on 28 November 2024, according to EY. The ATO says it applies to reporting periods starting on or after 1 July 2024. It covers groups, known as CBC reporting parents, with annual global income of $1 billion or more, where $10 million or more of aggregated turnover for the period was Australian-sourced.

Australia is always reported separately. Other jurisdictions are reported individually if they are on a list set by the Minister in a legislative instrument, which includes Singapore and Switzerland. The rest can be reported in aggregate. The required information includes, according to MinterEllison:

  • Main Business activities and the number of full-time-equivalent employees
  • Revenue from unrelated parties and from related parties not resident in that jurisdiction
  • Profit or loss before income tax
  • The Book Value of tangible assets, excluding cash
  • Income tax paid and income tax accrued for the current year
  • Reasons for any gap between tax accrued and tax at the local rate
  • The names of group members and a description of the group's approach to tax.

The point of the disaggregated figures is to let the public compare, Jurisdiction by jurisdiction, where a group books Revenue and profit, where its staff and Assets sit, and how much tax it pays there.

The ATO says completing all applicable fields fully and accurately helps avoid publication delays.

Registration and lodgment: the steps before the deadline

The new deadline comes with a less obvious requirement. The ATO says groups should register "at least 4 weeks before publishing your first Public CBC report." Registration is also needed for groups planning to apply for an exemption, exclusion or deferral.

Four weeks before 29 January 2027 is 1 January 2027, which is a public holiday. In practice, a group that wants to use the full deferral would need to register before the Christmas and New Year break.

The ATO says registration "helps streamline administration."

The ATO is also strict about format. Reports must be lodged electronically as an approved XML file, generated by the group's business software or a digital service provider. They are emailed to [email protected], with only one attachment per email, or the submission cannot be validated.

"Paper submission of the Public CBC report will not be accepted," the ATO says. Late publication may attract penalties, and the ATO says "Penalties may apply for non-compliance," without giving amounts on that page.

Hypothetical example: two groups, two deadlines

Hypothetical example: Group A has a reporting period that matches the calendar year. Its first period under the regime ran from 1 January 2025 to 31 December 2025. Twelve months later, its report would be due on 31 December 2026. The automatic deferral moves that to 29 January 2027, 29 days later. To publish on that final day, it would need to have registered by 1 January 2027.

Group B has a June year-end. Its period from 1 July 2024 to 30 June 2025 had a 12-month deadline of 30 June 2026. The automatic deferral described by the ATO covers only periods from 1 January to 31 December 2025, so it does not apply to Group B's report. Group B would need to have sought any extra time separately.

The example shows why the first public data is likely to arrive in stages rather than all at once.

What to watch and key dates

This is administrative guidance from the ATO on deadlines and process. It does not change who must report or what must be reported under the law.

  • Late December 2026: practical cut-off for calendar-year groups to register at least four weeks before a 29 January publication.
  • 31 December 2026: original due date for reports covering 1 January to 31 December 2025.
  • 29 January 2027: deferred deadline for those reports.
  • Early 2027: the first substantial batch of public reports could appear on data.gov.au, depending on ATO validation.
  • After publication: any amended reports if groups find material errors.

When the data arrives, it is likely to be scrutinised by tax transparency advocates, journalists and investors comparing where multinationals report profits against where they pay tax.