The top marginal income tax rate of 45% begins to apply to taxable income above $190,000 for an Australian resident individual in the 2025-26 financial year. That is, the top bracket starts at $190,001 (income exceeding $190,000). The Medicare levy is separate and is not included in this figure.

Working: For 2025-26 the resident individual rate scale is - nil to $18,200 (0%); $18,201 to $45,000 (16%); $45,001 to $135,000 (30%); $135,001 to $190,000 (37%); and $190,001 and above (45%). The 45% top bracket therefore commences at the threshold of $190,000 (applying to each dollar of taxable income above that amount).

Controlling authority: the rates of tax for resident individuals are set by the Income Tax Rates Act 1986 (Cth), specifically the resident rate scale declared in Schedule 7, Part I of that Act. (The Income Tax Assessment Act 1936 and 1997 impose and assess the tax, but the marginal rates and bracket thresholds are fixed by the Income Tax Rates Act 1986.)