Compliance

How to Estimate Irregular Freelance Income for Your August IRP6

Your first provisional payment for 2026/27 is due 31 August — six months into a year you can't fully see. A practical method for estimating irregular income: annualising the half-year, adjusting for known changes, and documenting the logic.

The August Problem

By 31 August, every provisional taxpayer must submit an IRP6 estimating their taxable income for the full 2026/27 tax year — a year that only ends on 28 February 2027. If your income were a salary, this would be arithmetic. For freelancers and contractors, it's a forecast: some months are double others, clients appear and disappear, and a single large project can reshape the year.

SARS knows this. What the law asks for is not clairvoyance but a genuine, defensible estimate. The difference between a defensible estimate and a guess is method — and a paper trail.

Start With What the Half-Year Actually Says

You have six months of real data: March through August (or close to it, by the time you sit down). Build the estimate from there.

Step 1: Total your actual income to date

Work from amounts invoiced and actually received, reconciled against bank statements. Include every income stream: client work, retainer income, once-off projects, rental income, taxable interest above the exemption.

Step 2: Annualise — carefully

The naive method doubles the six-month figure. That works only if your income is roughly even through the year. Refine it:

  • Known seasonality — if your busy season is ahead (or behind), weight accordingly. Look at last year's monthly pattern as a template.
  • Contracted work — retainers and signed projects for September–February are not speculative; put them in at contract value.
  • Pipeline honesty — probable-but-unsigned work belongs in the estimate at a discount, not at full value and not at zero.
  • Known losses — a client who gave notice, a retainer ending in December: subtract what's genuinely gone.

Step 3: Deduct expenses on the same basis

Estimate the full-year deductions you can support: home office running costs, business travel from your logbook, equipment wear and tear, professional fees, insurance, retirement annuity contributions under s11F (up to 27.5% of the greater of remuneration or taxable income, capped at R430,000). Half-year actuals doubled, adjusted for known one-offs, is the same logic applied to the cost side.

Step 4: Arrive at taxable income, then tax

Income minus deductions gives estimated taxable income. Apply the 2026/27 individual tax table and rebates to get the year's tax, deduct any PAYE already withheld by clients, then divide the remainder in half for the first payment. The IRP6 form walks through this structure; the quality of what comes out depends entirely on the taxable income figure you feed it.

The Basic Amount: Floor, Not Strategy

Your IRP6 arrives pre-populated with the basic amount — broadly, the taxable income from your most recent assessment, escalated by 8% per year where that assessment is older than 18 months. For the first period, paying on the basic amount is permitted and safe from an underestimation penalty perspective.

But treat it as a floor, not a strategy:

  • If your income has grown, the basic amount defers the true cost of your year to February — when the balance lands as one large payment, with the paragraph 20 penalty rules now in play.
  • If your taxable income will exceed R1.8 million, the second period safe harbour tied to the basic amount falls away entirely under the 2026/27 rules — your February estimate must track actual taxable income closely. Starting August near the truth makes February manageable.
  • If your income has dropped, you may estimate below the basic amount — but SARS may query a first-period estimate lower than the pre-populated figure, so keep the evidence of the decline.

Document the Logic

Keep a one-page working paper: income to date, the annualisation assumptions, contracted work included, deductions claimed, and the resulting taxable income. Date it.

This does two jobs. If SARS ever asks how you arrived at the estimate — which it may, particularly for second period estimates — you have a contemporaneous answer. And in February, when you must refine the estimate against ten-plus months of actuals, you'll adjust an existing model instead of starting over.

A Worked Example

A UX consultant invoices R310,000 from March to August. A signed retainer adds R40,000 a month from October through February (R200,000), and she expects roughly R60,000 of further ad-hoc work at a conservative discount. Estimated turnover: R570,000. Documented deductions — home office, equipment wear and tear, professional insurance, and RA contributions of R70,000 — total R150,000. Estimated taxable income: R420,000.

Tax on R420,000 per the 2026/27 table, less the primary rebate, gives the year's liability; half of that, less any PAYE, is her August payment. When one pipeline project fell through in January, her February estimate dropped the R60,000 ad-hoc line — a five-minute adjustment to a model she'd already built, documented on the same working paper.

The Deadline Discipline

The IRP6 must be submitted and the payment cleared by 31 August 2026. Submit a few days early: eFiling slows near the deadline, and a payment that reflects after the due date is a late payment attracting a 10% penalty, regardless of when you initiated it. An estimate built this week beats a perfect one built on deadline night.

Frequently asked questions

What happens if my first IRP6 estimate turns out to be wrong?

The first period estimate is not penalised for inaccuracy in itself — the underestimation penalty in paragraph 20 is tested against your second period estimate in February. But a low first payment pushes more of the burden onto February and can trigger interest, so a genuine, documented estimate is still in your interest.

Can I just use the basic amount SARS pre-populates on my IRP6?

You may use the basic amount for the first period, and for many taxpayers it is a sensible floor. But if your income has grown materially, paying on a stale basic amount defers a large true-up to February — and if your taxable income exceeds the R1.8m threshold, the basic amount offers no protection for the second period estimate.

Should I estimate high or low on my August IRP6?

Estimate honestly, then round up modestly if cash flow allows. Overpayments are recovered when your ITR12 is assessed, while underpayments attract interest and concentrate risk in the February estimate.

Allan Lombard Chartered Accountant · Founder, InspiredTax Africa

Allan has spent years working with South African provisional taxpayers and independent professionals. InspiredTax Africa was built to make year-round tax planning accurate, private and genuinely usable between the two IRP6 deadlines.

This article is general guidance on South African tax practice, not tax advice for your circumstances, and InspiredTax Africa is not affiliated with SARS. Verify figures against the current SARS tables before you file.

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