Twice a year, directors face the IRP6 return, and too often it becomes a last-minute guess: take last year's number, add a percentage that feels right, and hope. There's a better way, and it takes about twenty minutes.
An estimate that's too low risks a 20% underestimation penalty plus interest if your final taxable income comes in more than 20% above what you declared. An estimate that's too high hands SARS an interest-free loan with your own cash. Either way, a rough guess distorts your cash flow projections for the rest of the year.
By month six of your financial year, typically August for a standard February year-end, your books should be current. Pull a detailed income statement for the first five months from Xero or Sage: turnover, cost of sales, operating overheads, all reconciled. If your accounts are running behind at this point, that's the real problem to fix first, since you can't build an estimate on data that isn't there yet.
Take your cumulative five-month net profit, divide by five for a monthly average, then multiply by twelve. This single calculation strips out guesswork and grounds your estimate in what actually happened, not what you hoped would happen. Watch your gross margin closely here: if it slipped in the first five months, the annualised figure should reflect that rather than assuming the rest of the year fixes itself.
A straight annualisation assumes every month behaves identically, which is rarely true. If you're expecting a seasonal spike, or you've hired staff who'll push up labour costs in the second half, layer those known changes onto the baseline. This turns a mechanical calculation into a genuinely defensible estimate, one you can support with documentation if SARS ever queries the submission.
Remember that SARS taxes adjusted taxable income, not accounting profit, so strip out non-deductible items like accounting depreciation and add back your wear-and-tear allowances before you finalise the number.
The value of an SOP is that it doesn't depend on memory. Document the three steps, assign who pulls the month-five report and who runs the annualisation, and use the same template every cycle. Once it's routine, the twenty minutes it takes replaces the anxiety that usually surrounds the deadline.
Pull a reconciled income statement for months one to five. This is the entire foundation of the estimate, so it needs to be accurate.
Annualise using the five-month average. Divide by five, multiply by twelve, and let the real numbers drive the figure.
Adjust for known future events. Seasonal spikes, new hires, or planned price changes should all be layered onto the baseline.
Document the process once. A repeatable SOP removes the panic and the inconsistency from every future IRP6 cycle.
A straight divide-by-five, multiply-by-twelve model will distort a seasonal business. Weight it instead: if the first five months typically represent 30% of annual turnover, divide your actuals by 0.30 to project the year.
You can, without justification, if your taxable income is under R1 million. If your business has grown, though, a lower basic amount leaves you under-provided for the final bill, so it's rarely the safer option in a growth year.
Your first IRP6 is due at the end of month six, before that month's books are typically closed and reconciled. Month five is the last fully accurate dataset available at submission time.
An annualised, adjusted estimate takes twenty minutes and removes the two real risks of guessing: a painful underestimation penalty or an interest-free loan to SARS. Build the SOP once and reuse it every cycle. For related tax guidance, see our blog.
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