Investment Income Tax Calculator
Calculate the extra Australian income tax payable when investment income such as interest, dividends or rent is added to your salary.
Your results
Calculation breakdown
- Extra tax
- Extra tax = tax on (salary + investment income) − tax on salary alone
Worked example
On an $85,000 salary, $5,000 of additional bank interest adds about $1,600 of tax, an effective rate of 32% on that extra income.
Assumptions
- Treats investment income as unfranked and fully assessable.
- Does not model capital gains discounts or franking credits.
How this calculator works
Enter your salary and additional investment income such as bank interest, unfranked dividends or net rental income to see the extra tax this income attracts at your marginal rate. It compares total tax payable with and without the investment income, using resident tax brackets and the Medicare levy.
Rates sourced from the Australian Taxation Office for the 2026–27 financial year. Last reviewed 14/08/2026.
Frequently asked questions
Does this handle franked dividends and franking credits?
No, this treats investment income as unfranked; use the Franking Credits calculator on this site for imputation credit scenarios.
Why is my investment income taxed at my marginal rate?
Investment income is added to your taxable income and taxed at your normal marginal rates, unlike capital gains which can get a discount.
Does this cover capital gains?
No, use the Capital Gains Tax calculator on this site for asset sale profits, which have different discount rules.
Editorial review and responsibility
Reviewed by the CalcAussie editorial team on 21 September 2026. Review scope: Method, Australian terminology, material assumptions, source links and user-facing limitations.
Calculator results remain estimates based on the figures entered. Check material decisions against current official information and report a suspected error so it can be reproduced and corrected.
Rates and thresholds are configured for the 2026–27 Australian financial year and should be reviewed when government settings change.
Results are estimates only and are not financial, tax, legal or credit advice.