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Singapore Corporate Tax Filing YA2026: Deadlines, Forms & Rebate
Published 2026-06-20
Quick answer: Every Singapore company must file its Year of Assessment (YA) 2026 Corporate Income Tax Return (Form C-S, Form C-S (Lite), or Form C) with IRAS by 30 November 2026 via the myTax Portal — even if it made a loss or was dormant. Most companies must also file an Estimated Chargeable Income (ECI) within 3 months of their financial year-end, unless they qualify for the waiver. Singapore’s corporate tax rate is a flat 17%, reduced in practice by the start-up or partial tax exemption. For YA 2026, companies also receive a 50% CIT Rebate (with a minimum S$2,000 Cash Grant for companies that employed at least one local employee in 2025), capped at S$40,000.
Corporate tax filing in Singapore is a two-part annual cycle — an early estimate (ECI) and a final return (Form C-S/C) — pegged to your financial year-end. Miss either and penalties follow, even for a dormant company. This guide explains the YA 2026 deadlines, which form to file, the tax rate and exemptions, and the rebate available this year.
All figures below are drawn from IRAS. Tax rates, rebates, and exemption thresholds change with each Budget, so confirm the current position on the IRAS corporate income tax pages before relying on them, or speak to a tax adviser.
Tax Return vs Annual Return: Don’t Confuse Them
Two different annual filings are easy to mix up. Your tax return (Form C-S/C-S (Lite)/C) goes to IRAS and reports your company’s income. Your annual return goes to ACRA and updates the public register. They are separate obligations with separate deadlines, and filing one does not satisfy the other.
Understanding the Year of Assessment
Singapore taxes companies on a preceding-year basis. The Year of Assessment (YA) is the year in which income is assessed, based on profits from the financial year that ended in the previous calendar year. So YA 2026 covers the financial year ending in 2025. For example, a company with a 31 December 2025 financial year-end is assessed in YA 2026.
Key YA 2026 Deadlines
| Filing | Deadline |
|---|---|
| Estimated Chargeable Income (ECI) | Within 3 months of your financial year-end (unless waived) |
| Form C-S / C-S (Lite) / C (YA 2026) | 30 November 2026, via myTax Portal |
The 30 November filing deadline is the same for all companies regardless of financial year-end. The ECI deadline, by contrast, depends on your own year-end.
Which Tax Form Do You File?
There is one corporate tax return, in three versions. You file the simplest one you qualify for.
| Form | Who files it |
|---|---|
| Form C-S (Lite) | Companies with annual revenue of S$200,000 or below that meet the Form C-S conditions — the simplest version |
| Form C-S | Companies with annual revenue of S$5 million or below that meet the qualifying conditions (Singapore-incorporated, only income taxed at 17%, not claiming certain reliefs) |
| Form C | All other companies; full supporting documents (financial statements, tax computation) must be filed |
Estimated Chargeable Income (ECI)
ECI is your estimate of the company’s taxable income for the YA, filed early so IRAS can raise an initial assessment. You file it within 3 months of your financial year-end.
ECI waiver: You do not need to file ECI if your annual revenue is S$5 million or below and your ECI is nil for the YA. Filing ECI also lets you pay the estimated tax in interest-free instalments by GIRO — the earlier you file, the more instalments you get.
The Tax Rate and Exemptions
Singapore’s headline corporate tax rate is a flat 17% on chargeable income. Two exemption schemes reduce the effective rate, especially for smaller companies:
| Scheme | Exemption (YA 2020 onwards) |
|---|---|
| Start-Up Tax Exemption (first 3 YAs, qualifying companies) | 75% exemption on the first S$100,000 of normal chargeable income, plus 50% on the next S$100,000 |
| Partial Tax Exemption (all other companies) | 75% exemption on the first S$10,000 of normal chargeable income, plus 50% on the next S$190,000 |
A qualifying new company enjoys the start-up exemption for its first three consecutive YAs, then moves to the partial tax exemption from the fourth YA onwards.
The YA 2026 CIT Rebate
On top of the exemptions, Budget 2026 granted a Corporate Income Tax Rebate for YA 2026 to help companies manage cost pressures. The parameters were subsequently enhanced:
The CIT Rebate is 50% of the corporate tax payable for YA 2026. Companies that were active and employed at least one local employee in 2025 (the “local employee condition”) receive a minimum benefit of a S$2,000 CIT Rebate Cash Grant. The total maximum benefit a company can receive from the rebate and cash grant combined is S$40,000. The rebate is applied automatically by IRAS — no application is needed.
Penalties for Late or Non-Filing
Filing is mandatory even if your company is loss-making or dormant. If you miss the deadline, IRAS may issue an estimated Notice of Assessment (NOA) based on its own estimate of your income — which you must pay even if it is higher than your actual tax. IRAS may also issue a notice to comply, offer a composition fee, or summon the company and its directors to court. Persistent non-filing can lead to a fine on conviction. Objecting to an estimated NOA does not extend the filing obligation — you still have to file the actual return.
How Assembly Works Can Help
Corporate tax is more than hitting the 30 November date — it is computing chargeable income correctly, claiming the right exemptions, and filing the correct form. Assembly Works prepares your tax computation, files your ECI and Form C-S/C with IRAS, and reviews the exemptions and rebates relevant to your circumstances. For ways to lower your bill legitimately, see our guide to tax planning strategies for Singapore SMEs.
Learn more about our Taxation service or contact us to get your YA 2026 filing handled correctly and on time.