Provisional Tax Calculator (IRP6): Payments & Penalty Risk South Africa

Anyone who earns income other than a normal salary that already has PAYE deducted. In practice that covers freelancers, sole proprietors and other small business owners, landlords, anyone with meaningful interest or investment income, company directors, and companies themselves. You can also be a provisional taxpayer while holding down a salaried job, if you earn other income on the side. You're excluded if you don't run a business and your taxable income stays under the tax threshold for your age, or if your only other income is interest, foreign dividends or rental and it totals R30,000 or less for the year.

The first payment is due six months into the tax year, at the end of August. The second is due at the end of the tax year, the last business day of February. A third, voluntary top-up payment can be made up to seven months after the tax year ends, by 30 September, to close any remaining gap before SARS issues your assessment. Deadlines shift to the prior business day when the date falls on a weekend or public holiday, so check the exact date on eFiling rather than assuming a fixed day of the month.

SARS wants half of the tax on your estimated taxable income for the full year, less any PAYE already deducted from a salary during those first six months. You declare your estimated full-year taxable income on an IRP6 return, SARS calculates the tax on it using the normal tax tables and your rebates, and you pay half of that figure, minus PAYE credited for the period. If PAYE alone already covers half the tax, nothing is due, but you still need to submit the return.

This one settles the full year. SARS wants the total tax on your estimated full-year taxable income, less all the PAYE deducted during the year, less whatever you already paid in August. You can revise your income estimate for this return, most people know their year's income more accurately by February than they did in August, and a lot rides on getting this estimate right, since it's the one the underestimation penalty is measured against.

Your basic amount is the taxable income on your most recently assessed SARS return, the ITA34 from your last completed tax year, not this year's estimate. If your February estimate is at least your basic amount, SARS cannot charge you the underestimation penalty, no matter how much higher your actual income turns out to be, provided your actual income doesn't exceed R1 million. If that assessment is more than 18 months old by the time your second payment is due, SARS requires you to increase it by roughly 8% for every year since, compounded, before you can rely on it.

If your February estimate turns out too low, SARS can charge an underestimation penalty once your return is assessed. For actual taxable income of R1 million or less, the penalty applies if your estimate was both below your basic amount and below 90% of your actual income. It's calculated as 20% of the extra tax you should have paid, on the lower of the tax on 90% of actual income or the tax on your basic amount, after subtracting what you actually paid across PAYE and both provisional payments. This is separate from any interest charged on the shortfall itself.

Yes, and it's a hard cliff, not a gradual scale. Once your actual taxable income for the year exceeds R1 million, the basic amount stops offering any protection at all, and your February estimate must reach at least 80% of actual income instead of 90%. Someone with a very large basic amount who assumed it would keep them safe can still be penalised heavily if their income crosses that line and their estimate doesn't keep pace. If you're anywhere near R1 million, estimate on the cautious side.

They're two separate charges. The 20% underestimation penalty is only about the accuracy of your February estimate, and the basic-amount safe harbour can eliminate it entirely. Interest is different, it's simply the cost of paying tax late, and it accrues on any shortfall from 1 October (seven months after the tax year ends) until SARS issues your assessment, currently at 10.25% a year. Being penalty-safe through the basic amount does not stop this interest clock, only actually paying the money does, whether through your provisional payments or the optional top-up.

It's worth considering if you paid less than your actual tax liability by February, whether because you used the basic amount and it turned out too low, or because your real income only became clear after your second IRP6 was filed. Paying the shortfall by 30 September stops interest from accruing on it, even though the underestimation penalty (if any) has already been determined by your February estimate and can't be undone by a later payment. There's no penalty for not making a top-up payment, it exists purely to save you interest.

Partially. It uses the standard monthly medical scheme fees credit (section 6A), but not the additional credit for large out-of-pocket medical costs (section 6B), which can only be claimed on assessment, not on an IRP6. It doesn't model foreign tax credits or a separate 10% late-payment penalty, which applies if a payment misses its deadline regardless of whether the estimate was accurate. These are stated simplifications, not oversights, add them by hand if they apply to you.

No, it's a free independent tool using the 2026/27 SARS tax tables and the Fourth Schedule's underestimation penalty rules to give you a reliable estimate. The 8% basic-amount escalation shown is an approximation of the exact 18-month rule. It doesn't replace SARS's own Guide for Provisional Tax or advice from a registered tax practitioner, especially if your income is close to the R1 million cliff or you're unsure which basic amount applies to you.