Review a Singapore corporate tax Notice of Assessment, pay on time and object within two months when the assessment is wrong.
Singapore corporate tax: When a Singapore company receives a corporate tax Notice of Assessment, it should check the year of assessment, income, deductions, chargeable income, tax rate, exemptions, rebates, credits and payment position against the filed return and tax computation. If the assessment is wrong, the company generally has two months from the notice date to object. The tax shown is still payable within one month unless an approved payment arrangement applies.
Put both dates into the calendar immediately. An objection does not suspend collection, and missing the objection deadline can make the assessment final.
Identify which notice was issued
A notice can follow an ECI filing, a corporate income tax return, an IRAS adjustment or a failure to file. Read the assessment description and year carefully. A company may receive more than one notice for the same year if IRAS later revises the assessment or if the company corrects an error.
The IRAS after-filing guide explains how to view notices and object. Save the notice with its issue date and download the return acknowledgement, filed form and tax computation used for that year.
Reconcile the assessed figures
Start with the company’s accounting profit and trace the tax adjustments to chargeable income. Check disallowed expenses, capital allowances, donations, losses, group relief, foreign-income treatment and any incentive or exemption. Then compare the assessed tax, rebate, credits, payments and balance due.
For YA 2026, confirm that the assessment reflects the rules applying to that year rather than a spreadsheet rolled forward from YA 2025. Where the company expected the corporate income tax rebate or cash grant, check how IRAS applied the measure instead of deducting it manually from the filed chargeable income.
| Notice field | Compare with | Common question |
|---|---|---|
| Year of assessment | Financial year and return acknowledgement | Is this the intended accounting period? |
| Chargeable income | Tax computation and filed form | Did IRAS accept or adjust the return? |
| Losses and allowances | Supporting schedules and prior-year balances | Were claims used, restricted or carried forward? |
| Tax credits | Foreign tax and payment records | Is each credit present and capped correctly? |
| Rebate and grant | Applicable YA rules and IRAS computation | Was the measure applied by IRAS? |
| Balance and due date | GIRO, prior payments and ledger | What must be paid within one month? |
Pay even when objecting
IRAS states that the tax in a Notice of Assessment is payable within one month from the date of the notice, notwithstanding an objection. Confirm whether the company has GIRO instalments or must make a full payment. Keep the payment confirmation and reconcile it to the tax ledger.
If the assessment is later reduced, IRAS can refund the excess. Withholding payment while waiting for an objection can lead to late-payment penalties and enforcement action. Treat the payment and objection as parallel tasks.
Object within two months
A company that disagrees must use the Revise or Object to Assessment service in myTax Portal within two months from the notice date. State the disputed item, proposed treatment, amount and reasons. Attach the computation and evidence needed to understand the position.
Do not submit a message that merely says the assessment is wrong. If the dispute concerns an expense, identify the transaction, business purpose, tax rule and supporting documents. If it concerns foreign tax credit, reconcile the foreign income, foreign tax, receipt and applicable limitation. The IRAS objection and appeal guide explains the process and response expectations.
IRAS may request further information. Reply by the date in the request or, where no specific date is given, within the period stated in the current guidance. Keep a correspondence log and assign one person to coordinate complete answers.
Handle estimated assessments differently
An estimated assessment may be issued where ECI or the annual return was not filed. The ECI guidance says the estimated tax is payable within one month and an objection to an estimated ECI assessment must be filed within two months. The company should also complete the missing filing and explain the failure.
Do not treat the estimate as a substitute for the return. Reconstruct the accounts and tax computation, file the correct information and show why the estimate should change. Our ECI waiver guide explains when non-filing may be valid.
A worked review
A company receives a notice dated 20 August showing S$68,000 payable. Its filed computation expected S$54,000 because a foreign tax credit was claimed. The reviewer checks whether the credit appeared in the filed form, whether the evidence was complete and whether IRAS adjusted it. The company calendars payment by 20 September and, if the position remains disputed, files a reasoned objection by 20 October.
If the missing credit was caused by the company’s own filing error, the submission should say so and provide the corrected computation. If IRAS disallowed the credit, the company should address the stated reason. In either case, payment remains separate.
Close the assessment file
Keep the notice, filed return, tax computation, review checklist, payment, objection, acknowledgement, IRAS correspondence and final revised notice together. Update carried-forward losses, capital allowances and tax credits only after the final position is known.
Where the issue requires formal legal interpretation or an appeal, Raffles Consulting Services coordinates with Singapore law firms with the relevant tax speciality. Escalate early because statutory dates are not extended by internal review.
The YA 2026 corporate tax calendar covers the wider filing cycle, and the return-form guide explains Form C-S, Form C-S Lite and Form C. The Corporate and International Tax Consulting hub connects tax compliance and cross-border issues.
A Notice of Assessment is not a filing receipt to archive unread. A short reconciliation, two protected deadlines and a complete objection file can prevent an ordinary review from becoming a final, unpaid or unsupported tax position.