i What this calculator does
Quick answer: See which bracket your next rand of trading profit falls into, what it costs in tax, and how much of a gain you actually keep. With the default inputs (annual salary and other income 540 000, trading profit for the year 50 000), it returns you keep of R33 535.00.
A marginal tax rate calculator answers the question that matters when you make a trading profit: how much of it do you keep. Your salary sets the bracket you start in, and the profit is taxed on top of it.
If SARS treats your trading as revenue rather than capital, the profit is added to your other income. A R50,000 gain can therefore be worth R39,500 to one person and R27,500 to another, purely because of where their salary already put them.
This calculator is for educational purposes only. Results are estimates and may vary depending on market conditions, spreads, commissions, platform settings, and exchange rates. It should not be considered financial advice.
How to use the Marginal Tax Rate Calculator
The inputs carry workable values from the start. Nothing has to be entered to get a number on screen.
- 1. Annual Salary and Other Income (R)
- 2. Trading Profit for the Year (R)
- 3. Your Age
- 4. Retirement Contribution (R a year) Deductible to 27.5% of income, capped at R430,000
- 5. How SARS treats the profit
The result panel reports:
- You Keep Out of
- Marginal Bracket Where your next rand falls
Alongside the headline figures, the calculator reports taxable income before, taxable income after, amount included, bracket before. Those are the numbers that usually explain why the headline result came out where it did.
You can see how the number was built: each step appears beneath the answer.
See also: Dividend Withholding Tax Calculator and Bracket Creep in South Africa: What the 2025/26 Tax Freeze Cost Taxpayers.
Common results
What the calculator returns as the annual salary and other income changes, with every other input at its default (trading profit for the year 50 000, your age 35, retirement contribution 40 500, how SARS treats the profit Revenue, taxed at your marginal rate).
| Annual Salary and Other Income | You Keep | Tax On The Profit | Marginal Bracket |
|---|---|---|---|
| R150 000 | R41 000.00 | R9 000.00 | 18% |
| R300 000 | R37 000.00 | R13 000.00 | 26% |
| R750 000 | R30 500.00 | R19 500.00 | 39% |
| R1 500 000 | R29 500.00 | R20 500.00 | 41% |
| R2 500 000 | R27 500.00 | R22 500.00 | 45% |
| R5 000 000 | R27 500.00 | R22 500.00 | 45% |
Figures used in this calculator
The South African constants this calculator relies on, with the page that holds the current value and the date it was last verified.
- Income tax brackets 2026/27: 18% to 45%, first bracket to R245,100, top rate from R1,878,601. Source: SARS Income Tax Tables (verified 27 September 2026).
- Primary rebate: R17,820 a year. Source: SARS Income Tax Tables (verified 27 September 2026).
- Tax threshold, under 65: R99,000. Source: SARS Income Tax Tables (verified 27 September 2026).
- UIF contribution: 1% each from employee and employer, ceiling R17,712 a month. Source: PAYE, UIF and SDL Reference (verified 29 September 2026).
- VAT: 15%. Source: VAT Rates and Registration Thresholds (verified 29 September 2026).
- CGT inclusion and exclusion: 40% inclusion, R50,000 annual exclusion. Source: Capital Gains Tax Rates and Exclusions (verified 15 October 2026).
- Dividends Tax: 20%. Source: Dividend Withholding Tax by Country (verified 27 September 2026).
- Single discretionary and foreign investment allowances: R2 million and R10 million a calendar year. Source: Exchange Control Allowances (verified 27 September 2026).
How the calculation works
The calculator takes five inputs: Annual Salary and Other Income, Trading Profit for the Year, Your Age, Retirement Contribution and How SARS treats the profit. Retirement Contribution: Deductible to 27.5% of income, capped at R430,000. The taxable before is R540 000.00 - R40 500.00 = R499 500.00. The included profit is R50 000.00 in full. The taxable after is R499 500.00 + R50 000.00 = R549 500.00. The tax on the profit is R114 727.00 - R98 262.00 = R16 465.00. The breakdown also lists other income, trading profit, SARS treatment and retirement deduction allowed.
A worked example in rand
With the default inputs (annual salary and other income R540 000, trading profit for the year R50 000, your age 35, retirement contribution 40 500 R a year and how SARS treats the profit Revenue, taxed at your marginal rate), the calculator returns a you keep of R33 535.00, out of r50 000.00 of profit. It also reports tax on the profit R16 465.00 and marginal bracket 36%. Double the annual salary and other income to 1 080 000 and the you keep moves from R33 535.00 to R29 500.00, the tax on the profit moves from R16 465.00 to R20 500.00 and the marginal bracket moves from 36% to 41%.
How to read the result
With these inputs the calculator's own verdict reads: "This profit pushes you from the 31% bracket into the 36% bracket." The verdict changes as the inputs cross the thresholds the calculator uses, and it is the fastest way to see which side of them you are on. The calculators apply the current year's SARS rates; the result changes on 1 March each year and after the February Budget, so a figure from last year is not a small error but a different tax year. The background to this calculation is in SARS Tax Season Dates.
The South African angle
Three things change the picture for a South African trader using the marginal tax rate calculator. A tax compliance status from SARS, required for the R10 million foreign investment allowance, takes days to weeks to obtain and is the reason large offshore transfers are planned, not improvised. The 2026 Budget raised several thresholds at once, including the tax-free savings limit and the retirement deduction cap, so calculators built on 2025/26 figures are now wrong by meaningful amounts. VAT at 15% is not charged on financial services such as brokerage or spreads, which is why no VAT line appears on a trading statement even though the broker is a VAT vendor. The figures behind these points, and the ones the marginal tax rate calculator itself uses, are on the SARS income tax tables.
Spotted an outdated figure? If a rate, limit or formula in this calculator no longer matches its source, email us the page and the source. A material correction is dated on the Updates Log.
Frequently asked questions
What is the difference between marginal and effective rate?
The marginal rate is what your next rand of income is taxed at. The effective rate is total tax divided by total income, which is always lower because the earlier brackets are taxed at lower rates. For deciding whether a trade is worth taking, the marginal rate is the relevant one.
How do I know whether SARS sees my trading as revenue or capital?
There is no fixed holding period. SARS looks at intention and the pattern of behaviour: frequency, use of leverage, holding period, and whether the activity is run like a business. Frequent leveraged trading almost always falls on the revenue side.
Does a bigger profit push my whole income into a higher bracket?
No. Only the portion above the bracket threshold is taxed at the higher rate. That is what the calculation here shows: the tax attributable to the profit, rather than a recalculation of everything you earn.
Can I reduce the rate by contributing more to retirement?
Up to a point. Contributions are deductible to 27.5% of the greater of taxable income or remuneration, capped at R430,000 a year. Increasing contributions lowers taxable income and can move you back into a lower bracket.
Is the R50,000 exclusion annual?
Yes, the annual capital gains exclusion applies once per tax year across all your capital gains, not per transaction. It only applies if the gain is capital in nature.
What about losses?
Revenue losses can generally be offset against other income, subject to ring-fencing rules for certain activities. Capital losses can only be offset against capital gains. That asymmetry is one reason the classification matters.
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