About the top 100 population
The top 100 population:
- consists of public and multinational businesses and Australian Prudential Regulation Authority (APRA) regulated super funds that have substantial economic activity related to Australia
- contains the largest contributors to corporate income tax, excise, and petroleum resource rent tax (PRRT) collections
- includes some of the largest remitters of GST.
The top 100 population is a significant contributor to total income tax collections. Based on 2024 income tax returns, top 100 economic groups paid about $53.8 billion or 37% of all corporate income tax.
We moderate the top 100 population annually having regard to several factors including the size of their Australian operations. We also review top 100 taxpayers annually and tailor our engagement based on the Action Differentiation Framework (ADF).
Note: In 2026, 82 economic groups were in the top 100 population. This number varies year-on-year and some groups have more than one taxpayer in the top 100 population. Accordingly, the annual number of entities reviewed under the justified trust program does not equal 100.
Since the commencement of the justified trust program in 2016, our justified trust ratings have provided an objective mechanism for organisations to test and assess the effectiveness of their own tax governance processes as well as understand their tax profile. Publishing our Top 100 findings report helps organisations understand how our assessment of their tax profile compares to their peers in the market.
Top 100 taxpayers that have obtained overall high assurance ratings can achieve reduced compliance costs and are less likely to have intensive tax disputes with us. They can also rely on our high assurance rating to mean that we will generally not apply compliance resources to issues over which we have justified trust.
Owing to their significance in the tax system, we continually monitor top 100 taxpayers. However, we tailor the intensity of our reviews having regard to several factors including the level of assurance attained.
Where top 100 taxpayers achieve high assurance for income tax, we continue to monitor their disclosures and tax outcomes with a focus on significant new transactions and business changes. Similarly, for GST we generally take a monitoring stance to the GST affairs of top 100 reporters who attain overall high or medium assurance in an initial review. We also conduct some targeted engagement to address GST issues arising from initial review of some taxpayers.
However, a justified trust rating is not ‘set and forget’. Every 4 years we conduct a tailored justified trust review to refresh our confidence in the taxpayer’s tax outcomes.
We remain focused on real time engagement. We currently have real time justified trust reviews in progress with 95% of the top 100 population for income tax. Of those 80% have no past year justified trust reviews outstanding.
We also continue to encourage taxpayers to engage early with us and to make disclosures when changes or events happen, prior to lodging their return. Mutual engagement on matters will provide confidence to taxpayers and us that the tax outcomes reported in their returns are appropriate, or conversely, there is an informed understanding of where there may be a difference of view. We encourage taxpayers to ensure that evidence supporting the tax treatment of significant transactions is readily available and provided to us in a timely manner to support early resolution of issues.
We have seen the number of pre-lodgment disclosures remain relatively steady across 2025 and 2026. However, the majority (about 75%) are from high assurance taxpayers. We will continue to work with taxpayers, particularly those not at high assurance, to make fulsome disclosures of significant business changes and transactions to us as soon as possible.
The Top 100 Pre-lodgment disclosure framework provides guidance on our expectations of taxpayers and how we will engage on these matters.
Justified trust and transparency
Tax compliance is a focus among boards, investors, customers and consumers, suppliers, community groups and other stakeholders of how organisations contribute to the communities in which they operate. Many see compliance as an important component of environmental, social and governance (ESG) performance indicators. We have observed that our justified trust ratings are leveraged by organisations to demonstrate their community and ESG credentials as part of their broader social licence to operate.
Although there remains a level of non-compliance by some organisations in this population which we continue to robustly address, the overall level of compliance is very high and more than the broader community understands. Sharing our ratings can help address the gap for organisations that have achieved high assurance.
Our results to date demonstrate that most large businesses do the right thing. We have a high level of willing participation by most large corporate groups. Currently 82% of top 100 taxpayers have obtained either a high or medium overall assurance rating for income tax and 98% for GST. We see examples of companies that have committed to long-term behavioural change, including restructuring, changing their business practices, and settling long-standing disputes with us.
We continue to see justified trust assurance ratings disclosed together with other contextual information to assist the community’s understanding of the tax contributions of the largest participants in the Australian economy. We encourage the continued adoption of tax transparency practices (including the disclosure of assurance ratings) which supports community confidence that the largest taxpayers are paying the right amount of tax.
Our approach
We apply the justified trust methodology and seek to obtain assurance on the following 4 focus areas:
- Appropriate tax risk and governance frameworks exist and are applied in practice. This includes the design and operational effectiveness of business systems to create, capture and report transactions correctly for GST purposes.
- None of the specific income tax or GST risks we have flagged to the market are present.
- Tax outcomes of atypical, new, or large transactions are appropriate.
- We understand why the accounting and tax results vary. We analyse the various streams of economic activity and how they are treated for taxation purposes. We also analyse the sales, acquisitions, and other data, and compare this to net GST paid.
In doing so our Top 100 justified trust program provides an important foundational level of confidence about tax compliance across the various behaviours identified in the Public and Multinational three-tier model.
The tax assurance report (TAR) documents our findings, including:
- areas of strong tax governance and areas where we recommend further enhancements or improvements to align with 'better practices'
- areas of economic and tax affairs over which we have a high level of assurance
- areas where we have concerns or where improvements can be made and how a higher level of assurance can be obtained, including any planned compliance action
- our future engagement approach
- whether we have been able to assure the tax outcomes from significant new transactions or significant changes to the taxpayer’s business activities.
These reports are complemented by the annual action differentiation framework ('ADF') letters where we highlight to senior executives what is working well and any areas of concern requiring attention.
The Supplementary annual GST return (SAGR) commenced from the 2024–25 financial year for large business that have had a GST assurance review.
We use information from the SAGR together with real-time disclosures to monitor GST compliance, maintain assurance and undertake more targeted and less resource intensive reviews for many taxpayers. We have further streamlined our engagement with eligible high assurance GST reporters through an assurance check-in review, which is less intensive than our refresh reviews.