Addy: working-holiday tax treatment overturned

[2021] HCA 34; S25/2021 · Court / tribunal finding

An individual’s tax appeal succeeded under the UK–Australia treaty’s non-discrimination provision after proceedings through multiple court levels.

Finding

The High Court allowed the appeal with costs, disapplying the more burdensome working-holiday tax treatment in this taxpayer’s circumstances.

Qualifications and outcome

An adverse interpretation of tax law is not itself a finding of misconduct or waste. This test case affected a wider group. The assessed liability and the marginal amount disputed must not be confused.

Agency response

The order reversed the relevant Full Court orders. Downstream refunds, actual legal spend and quantified costs payments have not been verified here.

Affected party

Catherine Victoria Addy · Individual

The Court identifies an individual working holiday maker, not a company or small-business taxpayer.

Estimated case cost — scenario only

AUD 21,500–209,000; 2 unpriced categories. Actual expenditure unknown.

Mixed comparison basis: legal work at a 2023 NSW ordered-cost benchmark; internal work at an explicitly assumed loaded hourly cost. No historical inflation adjustment. Actual hours, panel discounts and internal staff grades remain unknown.

Sources

• Addy v Commissioner of Taxation — official judgment

  The High Court’s reasons, orders and named representation for the June 2021 hearing.

• Case S25/2021 — court file index

  Official procedural timeline and stated tax comparison: $3,986 assessed against a $1,591.44 comparator.

• NSW ordered-cost benchmark, 24 October 2023

  Non-binding legal rate bands for costs assessment. These are comparison rates, not the ATO’s invoices or historical engagement terms.