IAS 8 Accounting Estimates vs Errors: Worked SAR Examples

IAS 8 accounting estimates vs errors: what actually changed?

IAS 8 accounting estimates vs errors becomes much easier when you stop asking only which account moved. Ask what the accountant knew, when that information was available, and why the recorded amount now needs to change.

Imagine two finance teams reviewing equipment. One receives genuinely new evidence that a machine will last longer. The other discovers that last year's depreciation was never posted, despite a complete asset register. Both will change an expense. Their reporting periods need different treatment.

The [IFRS Foundation's IAS 8 overview](https://www.ifrs.org/issued-standards/list-of-standards/ias-8-basis-of-preparation-of-financial-statements/) distinguishes estimate revisions arising from new information from errors involving reliable information available when earlier statements were authorized and reasonably obtainable for their preparation.

Use this small decision table before opening your spreadsheet:

These are decision prompts, not substitutes for reading the transaction. A manager calling something a revision does not establish its classification. Keep the original calculation and the new evidence together.

The examples below use fictional Saudi businesses and amounts in SAR. They focus on financial reporting, with taxes and impairment excluded by assumption. They assume full IFRS Accounting Standards and no early adoption of IFRS 18. Review the applicable reporting framework before transferring the workings into a real engagement.

IAS 8 accounting estimates vs errors: which period takes the effect?

Prospective treatment starts from the change in estimate. It can affect the current period alone or the current and future periods. It does not mean postponing a change until the next financial year.

An estimate might change the carrying amount of an asset or liability, or relate to equity. Do not turn the shortcut “prospective” into a claim that every estimate revision must be an expense. The relevant item and standard still determine the accounting.

For equipment, distinguish the measurement from its inputs. Remaining useful life and residual value feed the [depreciation](/glossary#depreciation) calculation. A revised input supported by new evidence can alter the remaining expense pattern without proving earlier charges wrong.

The IFRS Foundation's [announcement of the estimate-definition amendments](https://www.ifrs.org/news-and-events/news/2021/02/iasb-amends-ifrs-standards-accounting-policy-disclosures-accounting-policies-accounting-estimates/) confirms their effective date for annual periods beginning on or after 1 January 2023. Older study notes may use the superseded definition, so check the edition you are reading.

Build a timeline with four boxes: asset available for use, earlier statements authorized, new information obtained, and revised calculation effective. Write the actual dates. If you cannot complete those boxes, you probably need more evidence before choosing a treatment.

For an asset reviewed halfway through a year, calculate the earlier portion using the assessment applicable then and the later portion using the revised assessment. Do not use hindsight to apply a December conclusion from January.

The next example deliberately starts its change on the first day of a year. That keeps the arithmetic clear while showing why a new remaining life is applied to the current carrying amount rather than to the original purchase cost.

Worked example 1: new evidence extends a Riyadh machine's life

Fictional Najd Office Services in Riyadh bought administrative equipment for SAR 240,000. It was available for use on 1 January 2023. The original useful life was six years, residual value SAR 24,000, and straight-line allocation appropriate. The 2023 and 2024 charges were correctly recorded.

On 1 January 2025, new operating conditions first arise and reduce expected future usage. An updated technical assessment supports five more years of use. Residual value remains SAR 24,000. Assume the new information did not establish an error in the earlier assessment and the equipment has no impairment.

First rebuild the balance immediately before the change:

The crucial number is five years remaining. It is not a new total life of five years from purchase. Write that wording beside the denominator.

The 2025 entry for this administrative equipment is:

Closing carrying amount is SAR 139,200. Compared with continuing the previous annual charge, 2025 expense is SAR 7,200 lower. After five revised annual charges, the remaining carrying amount will be SAR 24,000, assuming no subsequent changes.

The review file should explain the technical evidence and quantify the current effect. A useful reader-facing note describes the revision and the SAR 7,200 decrease in current expense; If assumptions stay unchanged, expense is also SAR 7,200 lower in each of 2026–2028, while 2029 carries SAR 28,800 instead of zero under the old schedule. These are comparison effects, not additional entries.

[IAS 16 paragraphs 51, 61 and 76](https://www.ifrs.org/content/dam/ifrs/publications/pdf-standards/english/2021/issued/part-a/ias-16-property-plant-and-equipment.pdf) address estimate reviews, method changes and related disclosure. If the underlying allocation is unfamiliar, revisit the [depreciation methods guide](/learn/how-to-calculate-depreciation) before rebuilding this schedule.

What makes an omitted charge a prior-period error?

Now change the evidence, not just the amount. Suppose the accountant had the purchase invoice, available-for-use date and approved calculation when preparing the earlier financial statements. The annual charge was omitted because the asset was excluded from a spreadsheet range.

That is a strong error indicator. Nothing new about the equipment's future was learned. The team failed to use information it already had. A correction label should describe that failure rather than hide it behind an estimate change.

For material prior-period errors, IAS 8 requires retrospective correction in the first financial statements authorized after discovery, subject to its impracticability provisions. Comparative figures for the affected periods are restated; errors before the earliest comparative period affect its opening balances.

This is also where [retained earnings](/glossary#retained-earnings) enters the discussion. An omitted prior expense may have overstated accumulated profit. But an opening ledger correction and a comparative presentation adjustment are two views of the same correction, not two separate expenses.

Draw one column for each reporting year, then show where the omitted charge belongs. Keep the current-year expense in its own column. This simple layout prevents a rushed “catch-up” entry from making current performance misleading.

Timing still matters. If the problem is found before the affected statements are authorized, correct those statements before issue. For the separate question of information arriving between year-end and authorization, use the [IAS 10 events-after-reporting guide](/learn/ias-10-adjusting-non-adjusting-events).

Do not assume an amount is immaterial because it looks small beside revenue. Consider its size, nature and the circumstances, including its effect on users' decisions. The worked error below explicitly assumes materiality so that the restatement mechanics can be followed without inventing a universal threshold.

Worked example 2: omitted depreciation in Jeddah's comparative figures

Fictional Red Sea Design in Jeddah acquired office equipment for SAR 120,000, available for use on 1 January 2024. Its documented useful life was five years with no residual value. The required annual depreciation was SAR 24,000.

The cost was recorded correctly, but no 2024 depreciation was posted. The omission was discovered on 1 July 2025, after the 2024 statements had been authorized. Assume the error is material, retrospective correction is practicable, and the 2025 statements show one comparative year.

The originally reported 2024 profit was SAR 100,000. Opening retained earnings were SAR 300,000, with no dividends or other movements. Rebuild the comparative column:

The 2024 opening position has no correction because the omission arose during 2024. Closing restated retained earnings of SAR 376,000 becomes the corrected opening balance for 2025.

If the 2025 ledger still carries the uncorrected opening balances, the following [journal entry](/glossary#journal-entry) represents the correction of that opening position:

This is a correction working, not an instruction to reopen a locked ledger without the entity's authorized process. If a reporting adjustment already corrects the same opening balance, reconcile it before posting to avoid duplication.

The separate total ordinary charge for 2025 is SAR 24,000: debit depreciation expense and credit accumulated depreciation. Correct accumulated depreciation at 31 December 2025 is SAR 48,000, leaving carrying amount SAR 72,000.

The error disclosure should explain the omitted charge and the comparative effects. The correction affects 2024 profit; it does not add another SAR 24,000 to 2025 expense. That final distinction is the most useful review check in this example.

How do you document policy questions, disclosure and missing evidence?

Write a short conclusion that someone else can reconstruct. For the first example, attach the earlier schedule, new technical report and revised remaining-life calculation. For the second, attach the original register, missing posting and comparative reconciliation.

A compact review sheet can contain:

• The transaction and affected financial statement lines.
• The information available when the earlier statements were authorized.
• The event or evidence that triggered this review.
• The classification and the reason for it.
• The current, comparative and opening-balance effects.
• The disclosures, reviewer and unresolved evidence requests.

For error disclosures, [IAS 8 paragraphs 49–53](https://www.ifrs.org/content/dam/ifrs/publications/pdf-standards/english/2021/issued/part-a/ias-8-accounting-policies-changes-in-accounting-estimates-and-errors.pdf) cover the nature of the error, corrections to affected lines, earnings per share where applicable, earliest opening effects, and limitations on retrospective restatement.

Impracticable requires more than an inconvenient search through old files. Document what was attempted and the earliest date a reliable correction can be made. Do not reconstruct an old estimate using later knowledge that was unavailable at the relevant time.

If the underlying measurement basis changes, investigate policy treatment separately. A new measurement technique or input does not automatically mean a new policy. Equally, a genuine error cannot become an estimate merely because the team prefers prospective treatment.

Finally, recognize the standard's evolving title. IFRS 18 moves requirements into IAS 8 and renames it Basis of Preparation of Financial Statements. The [official IFRS 18 page](https://www.ifrs.org/issued-standards/list-of-standards/ifrs-18-presentation-and-disclosure-in-financial-statements/) gives an effective date of annual periods beginning on or after 1 January 2027, with earlier application permitted. Check adoption status rather than inferring it from a website heading.

What common mistakes should your review catch?

Recalculating the past using a new remaining life. In the Riyadh case, the earlier SAR 72,000 accumulated charge remains valid. Dividing original cost by the revised remaining years would erase the logic of the change date.

Combining the missed charge and current expense. In the Jeddah case, a SAR 48,000 charge to 2025 expense would mix two years. Separate the comparative correction, opening position and normal current-year charge.

Posting the same correction twice. A consolidation worksheet may already contain the opening adjustment. Agree which layer owns it, then reconcile the ledger and reporting workbook before finalizing the figures.

Calling every unfavorable result an error. An outcome that differs from a reasonable forecast does not, by itself, establish misuse of earlier information. Ask for the evidence supporting the original estimate.

Treating every late discovery as a new estimate. A forgotten formula, omitted asset or ignored document may point to an error even when the discovery happens much later.

Stopping when debits equal credits. Both the correct and incorrect timing entries can balance. Your review must also establish the reporting period and resulting profit and asset balances.

Using a generic disclosure. “The company revised estimates” does not tell a reader what changed in this case. Connect the explanation to the equipment, evidence, affected amounts and periods.

Give each mistake its own review question. For example: “Does this opening adjustment already exist elsewhere?” is more useful than a checklist item saying “Check accuracy.” Specific questions make review work easier to repeat.

How can you practise the decision with Accountery?

Start with the two cases above and cover the answer tables. On a blank page, write the classification before calculating anything. Then explain which fact would have to change for the classification to change.

For the Riyadh case, rebuild the opening carrying amount and revised annual charge. For the Jeddah case, prepare the comparative profit bridge, opening correction and current-year expense separately. Check the ending equipment balance without looking at the example.

Next, change one fact at a time. Move the useful-life revision to the middle of a year. Or make the omitted charge relate to a period before the earliest comparative year. Keep a note of which part of your answer changes and why.

A useful study session has three outputs: a short evidence timeline, a balanced posting where required, and a sentence explaining the financial statement effect. A correct amount with no period explanation is an incomplete rehearsal of the work.

Use the [adjusting entries guide](/learn/adjusting-entries-guide) to refresh the posting mechanics, then continue with [Accountery practice exercises](/practice) and select available journal-entry or depreciation exercises. Apply this article's timeline and reconciliation method in your own workings alongside the exercise.

Keep a small error log with four labels: classification, calculation, posting and presentation. Rework the relevant part after reviewing feedback, then solve a fresh variation later. This helps you see whether the difficulty is the arithmetic or the accounting judgment.

Before calling an answer finished, explain it aloud to another learner: what changed, what information supports that conclusion, and which period carries the effect. If those three points are clear, the numbers become much easier to defend.