Estimating variable consideration in revenue

How a client estimates rebates, bonuses and other variable amounts in a contract price under IFRS 15, and when part of the estimate must be held back.

By Achekam · 11 October 2026 · 5 min read · For Accountants & audit firms in South Africa, Nigeria, Kenya

A distributor's contract promises its biggest customer a rebate once annual purchases pass an agreed level. A construction client earns a bonus if it hands over a building early and pays a penalty if it is late. A software reseller gives credits when uptime falls short. In each case the invoice says one thing and the amount the client will finally keep may be another.

At year end, the firm preparing or auditing those statements has to decide how much revenue the client can actually recognise. Booking the full invoiced amount overstates revenue if rebates are likely. Waiting until every uncertainty clears understates it. IFRS 15 sets a middle path, and it rewards clients who keep good records of how their customers behave.

When a price counts as variable

IFRS 15 has a client recognise revenue to depict the transfer of goods or services to the customer in an amount that reflects the consideration it expects to be entitled to in exchange. That amount is the transaction price. Where the promised consideration includes a variable amount, IFRS 15 requires the client to estimate the amount it expects to be entitled to.

Variability does not need to be written as a formula. Common sources in practice:

• volume or loyalty rebates that depend on what the customer buys over a period;
• performance bonuses and late-delivery penalties;
• price concessions the client habitually grants even though the contract does not mention them;
• credits for service failures;
• refunds when goods are returned.

The test is whether the amount the client keeps depends on something that has not happened yet. If it does, the estimate is needed.

Expected value or most likely amount

ACCA's technical article revenue revisited explains that IFRS 15 has variable consideration estimated as either the expected value or the most likely amount. The choice is about which method better predicts what the client will be entitled to.

Thinking it through for a client:

• Many similar contracts with a spread of outcomes. A retailer's returns across thousands of sales, or a wholesaler's rebates across many customers, behave like a population. A probability-weighted view across the range, the expected value, usually describes them better.
• One contract, two outcomes. A builder either earns the early-completion bonus or does not. Averaging the two gives a figure that can never actually happen, so the single most likely outcome is often the better predictor.

Whichever method is chosen, apply it consistently through the contract, and write down why it was chosen.

Holding part of the estimate back

Estimating is only half the step. ACCA explains that variable consideration is included in the transaction price only to the extent that it is highly probable that a significant revenue reversal will not occur. This is the constraint, and it is where judgement gets tested.

Questions worth putting to the client before accepting its estimate:

1. Does the outcome depend on things the client cannot control, such as the customer's own sales, the weather or a regulator's decision?
2. How much experience does the client have with this kind of contract, and is that experience still relevant?
3. How long until the uncertainty is resolved?
4. Is there a wide range of possible outcomes, or only a few?
5. Has the client a habit of granting concessions beyond what the contract says?

Several "yes" or "uncertain" answers point towards holding more back. The amount held back is not lost: it is recognised when the uncertainty clears.

Volume rebates that straddle year end

Rebates are where most firms meet this in practice. Take a wholesale client whose customer earns a rebate on all purchases for the calendar year once its total buying passes an agreed level, and whose financial year ends part way through that rebate year.

At the client's year end, the customer is some way towards the level. The firm needs to know:

• what the customer has bought so far and what its ordering pattern suggests for the rest of the rebate year;
• whether customers of this kind usually reach the level;
• whether the rebate applies back to the first unit once the level is reached, which makes the estimate more sensitive.

If it is highly probable that the customer will reach the level, revenue to date is recognised net of the expected rebate and a liability is shown for what will be owed. If reaching the level is genuinely uncertain, the constraint may still require part of the rebate to be accounted for, because recognising the full price could lead to a significant reversal. The reasoning, the data used and the conclusion should be on the working paper. A related question, how prompt-payment discounts are handled, is covered in settlement discounts in revenue.

Recording it in Achekam

The estimate lives in the firm's working papers; the accounting goes into the statements through the Studio.

• The adjustment. Staff can post a year-end adjusting entry in Achekam's Studio, for example reducing revenue and raising a rebate liability. If the entry is later found to be wrong, it is reversed with a record of who reversed it and why, so the trail stays intact rather than disappearing.
• The policy. The Studio's standard accounting policy wording is based on IFRS for SMEs and labelled for review before issue. For a client reporting under full IFRS, the revenue policy describing how variable consideration is estimated and constrained is one the firm writes or adapts itself, and staff can write their own policies in the Studio.
• The notes. Notes take their figures from the mapped trial balance. If the rebate liability sits in its own account and is mapped correctly, the note picks it up. Facts the trial balance does not hold, such as a description of the significant judgements, are left as "[to be completed]" for someone to write.

What the disclosure should tell readers

Users of the statements need to understand that revenue includes estimates. In plain terms, the notes should describe the kinds of variable consideration the client has, how it estimates them, how the constraint was applied, and the liability carried at year end for rebates or refunds. Where the judgement is significant, say so.

Refunds and product returns raise their own measurement questions, which warranty and refund provisions takes further.

For the next year-end file, ask each revenue client one early question: is there anything in your contracts, or in how you treat customers, that changes what you finally keep? The answer decides whether this analysis is needed at all.

General guidance only, not advice on your own circumstances. Tax and payroll rules change: check the current position with the authority or your adviser.