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  • Top 100 GST assurance program

    This program seeks greater assurance that top 100 taxpayers are reporting the right amount of goods and services tax (GST). This supports and expands on existing compliance approaches, including justified trust reviews for income tax, further enhancing confidence in these taxpayers.

    Under the program, GST and income tax teams are working collaboratively to deliver justified trust assurance reviews across both taxes. The extent that the assurance reviews will be integrated will vary. This will depend on the overall assurance rating in the most recent income tax assurance review, and whether we are maintaining or obtaining justified trust as part of our engagement approach.

    See also:

    How we tailor our compliance approach

    We gain assurance or identify areas of GST risk by engaging with the taxpayer through a 12-month GST assurance review.

    We will notify the taxpayer before we commence a review, and provide time for them to consider making a voluntary disclosure of any tax concerns.

    During a review we apply our justified trust methodology and tailor our compliance activities to the circumstances of the taxpayer, including:

    • the taxpayer’s overall GST performance
    • the type and size of business activities
    • GST risk management and governance
    • our understanding of the taxpayer from prior engagements including income tax assurance reviews.

    In a GST assurance review we look for assurance that:

    • appropriate GST risk and governance frameworks exist and are applied in practice
    • none of the GST risks we have flagged to the market are present
    • the GST outcomes of atypical, new or large transactions are appropriate
    • we can understand and explain the various streams of economic activity and how they are treated for GST which may include applying the GST analytical tool.

    A GST assurance review will focus on the last complete financial year. It will include systems and business activity statement (BAS) walkthroughs. Transaction testing is also undertaken, focusing on three consecutive BAS periods.

    We are currently developing and testing a GST analytical tool (GAT) to help us better understand why accounting and GST results vary. It is not intended for use by taxpayers with predominantly input tax supplies. Different analytical approaches are under consideration for these taxpayers.

    For a copy of the GAT Guide and method statement we use to complete our GAT calculations, email

    What to expect following a review

    Following a top 100 GST assurance review we will share our findings with you, including:

    • discussing the areas where we have assurance you reported the right amount of GST
    • any identified GST risks.

    We may recommend specific actions to gain greater assurance in particular areas. We will follow up on these recommendations as part of the annual compliance arrangement (ACA) and pre-lodgement compliance review (PCR) processes.

    If we identify concerns or areas of GST risk, we will work with you to gain greater assurance or address identified concerns or GST risks. There may be circumstances where we will take a different approach, such as an audit.

    See also:

    More information

    To learn more about the top 100 GST assurance program, email us at

    We welcome feedback as we continue to integrate our approaches for justified trust across income tax and GST. We are working on additional guidance to support taxpayers and their advisors in justified trust reviews, particularly regarding GST governance, systems and transaction testing.

    Last modified: 25 Oct 2019QC 60473