- Treasury appointed Katrina Di Marco as its new tax boss on September thirteenth, twenty twenty-six.
- She will lead work on capital gains tax and trusts tied to the May federal budget.
- Diane Brown said in July twenty twenty-six she would step down the following month.
Treasury appointed deputy secretary Katrina Di Marco as its new tax boss, replacing outgoing revenue-group deputy secretary Diane Brown in a change reported on September 13, 2026.
The appointment puts a senior Treasury official in charge of work on two tax files tied to the government’s budget program. Di Marco will serve in the department’s revenue group.
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Treasurer Jim Chalmers is working through the changes. The files concern capital gains tax and trusts.
The personnel change comes as Treasury moves from the announcement of the measures toward refining their settings. Di Marco will take over that work from Brown as the government develops the budget-linked tax measures.
Di Marco will steer Treasury’s work on two budget tax files
The May federal budget announced changes involving capital gains tax and trusts. Those measures form the core of the tax work now assigned to the new revenue-group deputy secretary.
Treasury’s role is to help shape the rules behind the measures. Di Marco is expected to steer the department’s work as officials implement or refine the budget’s revenue measures.
The two files sit together within the new assignment. One concerns capital gains tax, while the other concerns trusts.
The appointment therefore places Di Marco at the center of the department’s work on those policy settings. Chalmers remains the Treasurer responsible for working through the changes at the government level.
Details of the measures will continue to be developed through that process. The appointment gives Treasury’s revenue group a new deputy secretary to manage the work.
Brown’s July decision set the timing for the handover
Brown said in July 2026 that she would step down the following month. That announcement established the timing for the transition from the outgoing revenue-group deputy secretary to Di Marco.
The handover follows an existing personnel decision rather than a newly announced tax measure. Treasury is changing the official responsible for the revenue group while the budget files move through further work.
Brown’s departure leaves Di Marco to handle the department’s role on the capital gains tax and trust measures. The assignment connects the leadership change directly to the government’s continuing budget work.
Treasury’s attention now turns to the settings needed to carry those measures forward. Chalmers will continue working through the policy changes as the department develops its advice and implementation work.
The tax files remain the practical focus of the new role. Capital gains tax and trusts are the measures Di Marco will steer within Treasury’s revenue group.
This article is for informational purposes only and does not constitute tax advice. Consult a qualified tax professional or CPA about your specific situation.
