Capital Gains Tax South Africa Explained: How to Calculate What You Actually Owe

If you have sold a second property, exited a share portfolio, or divested from a family business, the last thing you want to encounter is an unexpected tax bill. For many South Africans, realising substantial wealth can be financially jarring when they discover that their profits are subject to Capital Gains Tax (CGT).

This guide demystifies CGT — explaining exactly what triggers it, how exclusions protect your assets, and how the inclusion rate determines your final liability so you walk away with maximum net proceeds.

What is Capital Gains Tax?

CGT is not a tax on income — it is a tax levied on the profit you make from disposing of capital assets. It is governed by the Eighth Schedule of the Income Tax Act and taxes the increase in value from a capital transaction (like selling property or shares), not the cash proceeds themselves.

A disposal is any instance where your interest in a capital asset ceases — including outright sale, donation, gifting, or a deemed disposal (such as death, where assets are considered sold at market value for tax purposes).

The Three-Step Calculation

Step 1: Calculate the Gross Capital Gain

Gross Gain = Sale Proceeds − Base Cost

The base cost is not just your original purchase price. It includes all documented capital improvements, renovations, and significant legal or transfer costs paid over the asset's lifetime. Keep every receipt.

Step 2: Apply the Annual Exclusion

SARS allows individuals an annual exclusion of R40,000 against any gains realised during a tax year. The first R40,000 of profit from disposals is exempt from CGT.

Step 3: Apply the Inclusion Rate

After deducting the annual exclusion, multiply the remaining taxable gain by the inclusion rate of 40% for individuals. Only this 40% portion is added to your taxable income and taxed at your marginal rate. CGT is therefore not a flat tax — it uses an inclusion rate added to taxable income, taxed at your personal marginal rate.

Taxable Capital Gain = (Gross Gain − Annual Exclusion) × 40%

Key Exclusions That Reduce Your Liability

Worked ZAR Example: Selling a Second Property

Jane sells her second property (not her primary residence) in Cape Town for R10,000,000. She purchased it 25 years ago for R3,000,000 and spent R500,000 on improvements.

1. Base Cost: R3,000,000 + R500,000 = R3,500,000
2. Gross Gain: R10,000,000 − R3,500,000 = R6,500,000
3. Less Annual Exclusion: R6,500,000 − R40,000 = R6,460,000
4. Taxable Capital Gain (40% inclusion): R6,460,000 × 40% = R2,584,000

Jane must declare R2,584,000 as additional income in her annual tax return. At a marginal rate of 45%, this adds approximately R1,162,800 to her tax bill. Planning the disposal across multiple tax years, or using the primary residence exclusion where applicable, can significantly reduce this liability.

Shares, ETFs, and the Trader vs. Investor Distinction

For shares and ETFs, SARS distinguishes between investors (long-term capital growth intent — CGT rules apply) and traders (frequent buying and selling for profit — treated as revenue income, taxed at full marginal rate). Accurate record-keeping documenting your intent and transaction history is essential.

Common Mistakes to Avoid

1. Ignoring improvement costs: Major renovations increase your base cost and directly reduce your taxable gain — include every documented capital expense.
2. Poor record-keeping: Without documentation, calculating accurate gains is impossible and SARS disputes become unavoidable.
3. Assuming all gains are exempt: Every disposal must be reviewed against the Eighth Schedule for applicable exclusions.

Conclusion: Plan Before You Dispose

Because CGT interacts with income tax and estate duty, expert guidance is essential when planning a major asset disposal. Use the Capital Gains Tax Calculator at /calculators/capital-gains to estimate your preliminary liability. If the asset forms part of an estate, also consult the Estate Duty Calculator at /calculators/estate-duty to plan for total tax exposure.

Disclaimer: This article is for educational purposes only and does not constitute financial or tax advice. Always consult a qualified SA financial adviser or tax practitioner.