How the TFSA calculator works
Last updated 9 November 2026
A tax-free savings account (TFSA) is any account or investment that SARS has approved as tax-free. You pay no tax on the interest, dividends or growth inside it, and none when you take money out. In return there are two limits on what you can put in: R 46 000 a tax year from 1 March 2026, and R 500 000 over your whole life.
The calculator steps through your plan month by month, one tax year (March to February) at a time. It adds each monthly contribution and any March lump sum, then grows the balance at the return you choose. Before it adds a contribution, it checks how much room is left under both limits.
If a contribution would go over a limit, the calculator leaves out the part that doesn’t fit and shows it as excess, with the 40% penalty SARS would charge if you made it. Growth never uses up any of your limits, so your balance can carry on growing long after you stop contributing.
Turn on “today’s money” to adjust every amount for inflation. That shows what the future balance would buy at today’s prices.
Worked example
Say you are starting from nothing and put in R 3 833.33 a month, the most that fits under the annual limit. You expect 9% a year. These are the calculator’s starting values.
- Each tax year you contribute just under R 46 000, so you never go over the annual limit.
- After about 11 years of contributions you hit the lifetime limit. In this example that happens in January 2037, during year 11.
- From then on, nothing more goes in. Your total contributions stay at R 500 000.
- After 20 years, the balance could be about R 1 912 397. Of that, R 1 412 397 is growth you never pay tax on.
Now say you plan R 5 000 a month instead. That is R 60 000 a year, which is R 14 000 over the annual limit. If you paid it all in, SARS would charge R 5 600 in penalties for that year alone.
What the figures mean
- Projected balance is what your account could be worth at the end of the period, with growth at the rate you chose and no fees.
- Total contributed is everything you have put in, including your contributions so far. This is the number the lifetime limit is measured against.
- Tax-free growth is the difference between the balance and your contributions.
- Lifetime limit reached is the month your total contributions hit R 500 000.
- Status in the table shows whether you still have room that year, hit the annual limit, or have reached the lifetime limit.
Things to watch
- The limits are per person, across every provider. Two accounts at different banks share one R 46 000 limit.
- Withdrawals don’t give you your room back. If you take out R 10 000 and put it back, that counts as R 10 000 of new contributions.
- The 40% penalty applies to the excess, even if it was a mistake. Keep track of debit orders that carry on after you reach a limit.
- If you leave the current balance at 0, the calculator starts from your contributions so far and ignores past growth, so your real balance may be higher. Enter today’s balance for a closer projection.
- Returns are not guaranteed. A TFSA that holds shares can go down in value, and fees reduce growth.
- Parents can open a TFSA for a child, but those contributions use up the child’s own lifetime limit.
To compare growth outside a TFSA, try the compound interest calculator. To work out a monthly amount for a specific goal, use the savings goal calculator.
Sources
The annual limit, lifetime limit and 40% penalty come from SARS’s page on tax-free investments and the Budget 2026 changes. All figures were last checked on 9 November 2026, and the full list of sources is at the bottom of this page.