Tax on Interest Income Calculator for South Africa (2026/2027)
Mzansify's free interest tax calculator for South Africa uses the SARS 2026/2027 interest exemption for your age group and the official brackets. Enter the interest you earned and your other income to see the taxable interest, the tax on it and what you keep. No sign-up, and your numbers never leave your browser.
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Last reviewed: Tax year: 2026/2027Source: SARS — Interest and dividends
Read the guide: Understanding South African Income Tax Brackets (2026/2027)
Example: R100,000 of interest on top of R400,000 of other income (under 65) leaves R76,200 taxable after the R23,800 exemption, which means R23,622 tax and R76,378 kept (2026/2027).
The interest exemption for 2026/2027
SARS exempts a slice of the interest you earn each year, and the exemption is bigger from age 65. Only interest above the exemption is added to your taxable income.
| Taxpayer | Interest exempt per year |
|---|---|
| Under 65 | R23,800 |
| 65 and older | R34,500 |
The exemption covers interest from a South African source, such as savings accounts and fixed deposits. Foreign interest does not qualify. Interest inside a tax-free savings account is exempt and does not use up the exemption.
How the tax on interest is worked out
Interest above the exemption is added to your other income and taxed at your marginal rate. The calculator works out the tax on (other income + taxable interest) minus the tax on other income, where other income means your other taxable income for the year after retirement-fund deductions (none is applied here), using the same engine as the income tax calculator, so rebates and medical credits are applied correctly.
Worked examples
Age 35, R100,000 interest
R400,000 of other income, no medical aid. 2026/2027 tax tables.
- Exemption for the age group
- R23,800
- Taxable interest
- R76,200
- Tax for the year without the interest
- R67,417
- Tax for the year with the interest
- R91,039
- Effective rate on the interest
- 23.6%
Age 70, R100,000 interest
R150,000 of other income, no medical aid. 2026/2027 tax tables.
- Exemption for the age group
- R34,500
- Taxable interest
- R65,500
- Tax for the year without the interest
- R0
- Tax for the year with the interest
- R11,205
- Effective rate on the interest
- 11.2%
Where to find your interest figure
Your bank or investment provider issues a tax certificate (IT3b) with the interest you earned in the tax year, and SARS pre-populates it on your return. If you also let out a property, see the rental income tax calculator.
Sources
Frequently Asked Questions
SARS exempts the first R23,800 of interest a year for people under 65 and the first R34,500 for people aged 65 and older in 2026/2027. Only interest above the exemption is added to your taxable income.
Interest above the exemption is added to your other income and taxed at your marginal rate. For example, R100,000 of interest on top of R400,000 of other income (under 65) leaves R76,200 taxable after the R23,800 exemption, and the extra tax is R23,622. "Other income" means your other taxable income for the year, after retirement-fund deductions.
No. Interest and growth inside a tax-free savings account are exempt and do not count towards the annual interest exemption. See the TFSA calculator for the contribution limits.
The exemption covers interest from a South African source, as the SARS interest and dividends page puts it. Interest from a foreign source does not qualify and is taxable in full, so keep it out of the figure you enter if you want the exempt amount to be correct.
The exemption depends on your age: it is higher for people aged 65 and older. This calculator uses your age at the end of the tax year (28 or 29 February), the same convention as the age rebates; the SARS interest page does not spell out the exact test date.
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