KEY REMINDER: THE YA 2026 CORPORATE INCOME TAX FILING DEADLINE IS 30 NOVEMBER 2026
Companies required to file their Year of Assessment 2026 Corporate Income Tax Return must submit it through the IRAS myTax Portal by 30 November 2026.
The YA 2026 return generally covers income, expenses, capital expenditure, assets, liabilities and tax adjustments relating to the company’s financial year ending in 2025. A company should not assume that its filing obligation has been satisfied simply because the financial year has ended or the previous year’s tax return was filed.
IRAS has stated that a company may still need to file even if it did not make a profit, incurred a loss, had no income or did not carry on business during the relevant financial year. A company should assess its filing status based on IRAS requirements and its account status rather than relying only on an internal view that it had “no business” or “no tax payable”.
Directors remain responsible for ensuring that the company’s Income Tax Return is filed accurately and on time. Engaging an accountant, tax agent or corporate secretary does not completely remove the directors’ responsibility. Late filing or non-filing may lead to an estimated Notice of Assessment, a composition amount, information requests to directors, court summonses and further legal action.
FIRST, CONFIRM THE COMPANY’S FILING POSITION
Before preparing documents, the company should confirm its operating status during the 2025 financial year and review its status in the IRAS system.
Company carried on business or received income in 2025
A company that carried on business or received income during 2025 will generally need to file its YA 2026 Corporate Income Tax Return by 30 November 2026. This remains the case even if the company ultimately reports a tax loss or has no tax payable.
Company was in a loss position
A tax loss does not automatically remove the filing requirement. A company that continued to operate or received income should normally file its return. It should calculate tax losses, unutilised capital allowances, donations, tax adjustments and any available carry-forward items accurately rather than entering the accounting loss directly into the tax return.
Company was dormant
Whether a dormant company must file depends on its status with IRAS.
If the company’s status is “No Business Done” and IRAS has granted a waiver from filing Corporate Income Tax Returns, the company generally does not need to file for that year.
If the company’s status is “Active”, it will generally need to file the Form for Dormant Company, even if it did not carry on business during the relevant period.
A company should not stop filing merely because management considers that it had no business. It should log in to myTax Portal and confirm its filing status and whether a filing waiver has been granted.
Company incorporated during 2025
Whether a newly incorporated company needs to file YA 2026 depends on its first set of financial statements, whether the first accounting period ended in 2025, and whether it commenced business or received income.
If the company closed its first set of accounts in 2025 and commenced business or received income during 2025, it will generally need to file.
If the company closed its first set of accounts but did not commence business or receive income during 2025, or if its first accounting period did not end in 2025, the filing position should be confirmed against the company’s actual circumstances and IRAS guidance.
CHOOSE THE CORRECT CORPORATE INCOME TAX FORM
Not every company uses the same Corporate Income Tax form. The company should select among Form C-S (Lite), Form C-S, Form C, the Form for Dormant Company or another applicable filing based on its revenue, tax position and claims.
Form C-S (Lite)
A company that qualifies for Form C-S and has annual revenue of no more than (SGD) 200,000 may choose Form C-S (Lite). This is a simplified form requiring only six essential fields and is intended for smaller companies with relatively straightforward tax affairs.
Form C-S
A company generally needs to meet all of the following conditions to use Form C-S:
•It is incorporated in Singapore;
•Its annual revenue is no more than (SGD) 5 million;
•Its income is taxable at the prevailing 17% Corporate Income Tax rate; and
•It is not claiming certain items, such as carry-back of current-year capital allowances or losses, Group Relief, Investment Allowance, Foreign Tax Credit or tax deducted at source.
Form C-S is a simplified filing form. “Simplified” does not mean that the company can operate without proper accounts or tax computations. The company should still prepare financial statements, a tax computation and supporting records, and provide them if IRAS requests them.
Form C
A company that does not qualify for Form C-S, Form C-S (Lite) or the Form for Dormant Company should file Form C.
A Form C filing generally requires more information, including:
•audited or unaudited financial statements;
•a detailed profit and loss statement;
•a tax computation and supporting schedules;
•Form IRIN 301, Additional Information on Income and Deduction;
•relevant Group Relief, research and development, capital allowance, intellectual-property or other claim forms; and
•other supporting documents required by IRAS.
If the company has Group Relief claims, foreign income, research and development expenditure, complex capital allowance matters, special-industry income, cross-border transactions or other special tax items, it should not choose Form C-S merely to reduce the amount of information filed.
DOCUMENTS TO PREPARE BEFORE 30 NOVEMBER
Companies should start building their YA 2026 filing package as early as possible. Late preparation increases the risk of omitted income, incorrect expense classification, missing documents and delays in obtaining director approval.
Financial statements and accounting records
Prepare the financial year 2025 balance sheet, profit and loss statement, cash-flow information, general ledger, trial balance and major account schedules. A small company that is exempt from statutory audit is not exempt from maintaining proper accounting records.
The financial statements should reconcile with bank statements, receivables, payables, inventory, fixed assets and shareholder or director balances. Pay particular attention to unrecorded accruals, prepayments, revenue recognition, bad debts, foreign-currency balances and related-party balances at year end.
Income records
Income should not be identified solely from bank receipts. Reconcile sales invoices, contracts, collection records, platform settlement statements, interest, dividends, rental income, commissions, service fees, royalties and other sources of income.
For cross-border sales, overseas customers, digital services or platform transactions, confirm the timing of income, contracting entity, place of performance and related tax treatment.
Expense and deduction records
Organise records for salaries, CPF contributions, rent, professional fees, software subscriptions, insurance, transport, marketing, interest, repairs, logistics and other operating expenses. Distinguish revenue expenses from capital expenditure.
Not every accounting expense is automatically tax deductible. Private expenses, capital expenditure, expenses not connected with income production, penalties and other non-deductible items may need to be added back or treated separately in the tax computation.
Fixed assets and capital allowances
Prepare records for assets acquired or disposed of during the year, including invoices, payment evidence, dates placed into use, asset categories and explanations of business use.
Accounting depreciation is generally not claimed directly as a tax deduction. The company should calculate capital allowances under the tax rules and confirm whether the assets qualify, whether they were brought into use and whether disposal gives rise to a balancing allowance or balancing charge.
Tax adjustments and prior-year items
Review unutilised tax losses, capital allowances, donations, foreign tax credits, Group Relief, withholding tax, research and development claims and other carry-forward items from earlier years.
These amounts should not be carried forward solely on the basis of an internal spreadsheet. Reconcile them to the IRAS Notice of Assessment, the previous year’s tax computation and the relevant filing acknowledgements.
Related-party and cross-border transactions
If the company transacted with group companies, directors, shareholders, related entities or overseas entities, prepare the contracts, invoices, payment records, pricing basis and balance confirmations.
Cross-border related-party transactions may involve transfer-pricing records, withholding tax, tax treaties, foreign tax credits and source-of-income questions. A transaction should not be ignored merely because the amount is relatively small.
GST and other tax records
GST-registered companies should reconcile GST returns with sales, purchases and accounting records. GST should not be incorrectly included in the income or expense base unless the specific accounting and tax treatment requires it.
The company should also review whether withholding tax applies to director fees, interest, royalties, overseas services, technical services, employee benefits or other payments.
HOW TO PREPARE THE TAX COMPUTATION
Corporate Income Tax is not calculated by simply multiplying accounting profit by the tax rate. The company must start from the accounting profit or loss and make the required tax adjustments to arrive at chargeable income or an allowable tax loss.
The process generally includes the following steps.
First, confirm that the accounting profit or loss agrees with the financial statements.
Second, add back items recorded in the accounts but not deductible for tax purposes, such as certain depreciation, private expenses, capital expenditure, non-deductible penalties and other disallowed costs.
Third, deduct qualifying items that were not treated as ordinary expenses in the profit and loss statement, such as applicable capital allowances, qualifying donations, research and development deductions or other permitted adjustments.
Fourth, consider partial tax exemption, start-up tax exemption, foreign tax credits, Group Relief, loss carry-forwards and other applicable items.
Fifth, reconcile the chargeable income, tax loss, amounts available for carry-forward and final tax payable.
The company should retain evidence supporting each tax adjustment. IRAS may ask why a particular expense is deductible, why a particular receipt is not taxable or why a capital expenditure item qualifies for capital allowances.
ECI AND THE ANNUAL CORPORATE TAX RETURN ARE DIFFERENT FILINGS
Many companies confuse ECI, or Estimated Chargeable Income, with the annual Corporate Income Tax Return. They are separate filing obligations.
ECI generally needs to be filed within three months from the end of the company’s financial year, unless the company qualifies for an ECI filing waiver or falls within a specific category that is not required to file ECI.
A company may qualify for an ECI filing waiver if its annual revenue is no more than (SGD) 5 million and its ECI for the YA is nil. The company must assess the conditions itself and does not need to obtain separate confirmation from IRAS if it qualifies.
An ECI filing waiver does not automatically mean that the company is exempt from the annual Corporate Income Tax Return. The company may still need to file Form C-S, Form C-S (Lite), Form C, the Form for Dormant Company or another applicable return by 30 November 2026.
If the company filed ECI and the chargeable income subsequently reported in Form C-S, Form C-S (Lite) or Form C is higher, the company should pay the additional tax within the applicable period after receiving the Notice of Assessment.
If the final chargeable income is lower than the ECI previously declared, any excess tax paid will generally be refunded or applied according to IRAS procedures.
DIRECTORS, CORPPASS AND TAX-AGENT RESPONSIBILITIES
Before the deadline, the company should confirm that its Corppass authorisation is properly set up. To file through myTax Portal, an employee or tax agent must be authorised as an Approver for the “Corporate Tax (Filing and Applications)” digital service.
The company should also confirm that:
•the director or tax agent can log in to myTax Portal;
•the company’s UEN or Entity ID is correct;
•authorised personnel who have left the company have been removed or replaced;
•the person submitting the return is authorised to approve and file it; and
•the company will retain the successful filing acknowledgement.
Engaging a tax agent can reduce operational and calculation pressure, but the company must still provide complete information and review significant tax judgments. Directors should not approve a filing without reviewing the key figures and material disclosures.
FORM C-S AND FORM C HAVE DIFFERENT DOCUMENT REQUIREMENTS
For Form C-S and Form C-S (Lite), the company should prepare financial statements, a tax computation, supporting schedules and relevant declarations. These documents should generally be retained and provided if IRAS requests them. If the company makes a specific claim, such as a writing-down allowance for intellectual property rights, the relevant declaration may need to be filed together with the return.
For Form C, the company generally needs to submit the financial statements, detailed profit and loss statement, tax computation and supporting documents electronically with the return.
All PDF attachments should be checked in advance to ensure they open correctly, contain every page, are legible and meet myTax Portal’s file requirements. The filing date should not be the first time the company tests its attachments.
WHAT IF THE COMPANY CANNOT FILE BY 30 NOVEMBER?
The safest approach is to complete the filing as soon as possible rather than wait for an IRAS reminder or estimated assessment.
If the company genuinely cannot complete the filing by the deadline, it may request an extension through myTax Portal where the applicable process is available. IRAS states that an extension request for the current YA generally becomes available only after 30 November. If a Notice to Attend Court or Summons has already been issued, the ordinary electronic extension process may not be available and the company representative may need to attend court to request more time.
Waiting for a tax agent’s reply or for financial statements to receive a final signature does not automatically extend the filing deadline. Management should distinguish between issues that affect the tax figures and documents that may be supplied later if IRAS requests them, and complete the filing within the permitted rules.
CONSEQUENCES OF LATE FILING OR NON-FILING
If a company fails to file its Corporate Income Tax Return, financial statements and tax computation by the deadline, IRAS may take several actions.
Estimated Notice of Assessment
IRAS may estimate the company’s tax based on previous-year income or other available information. It may assume that the company’s income has increased. If the company receives an estimated Notice of Assessment, it generally must pay the estimated tax within one month from the date of the notice, even if it intends to object to the assessment.
Composition amount
IRAS may offer the company the option of paying a composition amount instead of commencing prosecution. The amount can be up to (SGD) 5,000 per offence, depending on the company’s compliance record and the circumstances. The company must still file the overdue return and documents by the specified date.
Information notice to directors
IRAS may issue a notice under Section 65B(3) of the Income Tax Act requiring a director to provide information by a specified date. Failure to comply may lead to further enforcement action.
Court summons and legal proceedings
If the company does not file the outstanding return or pay the composition amount, IRAS may issue a Notice to Attend Court or Summons to the company or persons responsible for running it, including directors.
If convicted for failing to file, the company may face a fine of up to (SGD) 5,000 per offence. A director convicted for failing to comply with a Section 65B(3) notice may face a fine of up to (SGD) 10,000, imprisonment for up to 12 months, or both.
If a company fails to file its tax returns for two or more years, the court may order the company to pay a penalty equal to twice the assessed tax, in addition to a fine of up to (SGD) 5,000 for each offence.
ACTION CHECKLIST BEFORE 30 NOVEMBER
The company can work through the following sequence.
First, confirm whether the company must file a YA 2026 Corporate Income Tax Return and whether any filing waiver is reflected in its IRAS status.
Second, confirm the financial year end, the status of the 2025 accounts and the 30 November 2026 deadline.
Third, confirm Corppass, Singpass, UEN and myTax Portal access.
Fourth, determine whether the company should use Form C-S (Lite), Form C-S, Form C, the Form for Dormant Company or another applicable form.
Fifth, complete the financial statements and reconcile the bank accounts, general ledger and major balances.
Sixth, organise income, expenses, fixed assets, capital allowances, GST, related-party transactions, cross-border transactions and tax-adjustment records.
Seventh, prepare the tax computation and reconcile carry-forward items to the previous Notice of Assessment.
Eighth, check whether ECI has been filed and whether there is a material difference between the ECI and the final chargeable income.
Ninth, prepare the financial statements, detailed profit and loss statement, tax computation, Form IRIN 301 and other supporting documents required for Form C.
Tenth, reserve time for an internal review and ensure that the director or authorised Approver submits the return before the deadline.
Eleventh, retain the filing acknowledgement, submitted return, attachments, tax computation and supporting documents.
The key deadline for Singapore Corporate Income Tax filing in 2026 is 30 November 2026. Companies should not treat the date as merely the deadline to upload a form. It is the final date for a complete review of financial data, tax adjustments and corporate compliance.
A company should confirm whether it has a filing obligation, choose the correct form, prepare financial statements and tax computations, review ECI and prior-year carry-forward items, set up Corppass authorisation and submit through myTax Portal on time.
A loss, dormant status, lack of income or prior ECI filing does not automatically remove the YA 2026 Corporate Income Tax filing obligation. A company may rely on a non-filing position only when it satisfies the applicable IRAS waiver or exemption conditions and its account status supports that position.
The most effective risk-control approach is to begin now, assign responsibilities clearly, prepare the document package and leave sufficient time for internal review. Filing on time, accurately and with proper supporting records will help the company avoid estimated assessments, composition amounts, court summonses and potential director-level compliance risks.
