A Comprehensive Guide to Filing Corporate Tax for Singapore Businesses in 2025
It’s the end of November, and you’re scrambling to gather your company’s financial documents to meet the looming tax filing deadline. The pressure mounts as you glance at your financial statements, spreadsheets, and invoices. While such a situation can be overwhelming to businesses, especially ones that haven’t filed corporate taxes before, don’t fret. With the proper knowledge and preparation, you can fulfil your tax obligations with confidence.
In this article, we provide all the essential information that you need to file the corporate tax for the 2025 season in Singapore.
Key Deadlines for YA 2025
First, you must adhere to the deadlines set by the Inland Revenue Authority of Singapore (IRAS) to avoid penalties or compliance issues:
Estimated Chargeable Income (ECI) Filing: Within 3 months from the end of your financial year.
Corporate Income Tax Return (Form C-S/Form C-S (Lite)/Form C): Due by 30 November 2025.
What Are the Forms?
The forms are documents used to file your taxes, chosen based on your company profile and circumstances. Filing a more comprehensive form than required (e.g., Form C instead of Form C-S (Lite)) won’t result in penalties but may trigger additional scrutiny and effort. Ensure you select the appropriate form:
Form C-S
This simplified tax return is designed for companies with straightforward tax matters. To qualify, your company must:
- Have an annual revenue of $5 million or less.
- Not claim any of the following:
- Carry-back of current year capital allowances or trade losses.
- Group relief.
- Investment allowance.
- Foreign tax credit.
- Tax deductions for donations.
Form C-S (Lite)
An even more streamlined version of Form C-S, Form C-S (Lite) is available for companies that:
- Have an annual revenue of $200,000 or less.
- Do not have any foreign income.
- Do not claim any of the deductions or reliefs listed above.
Form C
If your company doesn’t meet the criteria for Form C-S or C-S (Lite), you’ll need to file Form C. This comprehensive form requires detailed financial statements, tax computations, and supporting schedules. 
Special Considerations for New Companies
For companies incorporated in 2024, the filing requirements for YA 2025 depend on the financial year-end and commencement of business activities:
- First Set of Accounts Exceeds 12 Months: If your company’s first set of accounts spans more than 12 months, you must apportion your profits/losses to the relevant YAs and file accordingly.
- First Set of Accounts is 12 Months or Less: If your company’s first set of accounts is 12 months or less, you may not be required to file for YA 2025. However, if your company commenced business or received income in 2024, you must request the issuance of the tax return and file it accordingly.
Filing for Dormant Companies
Even if your company was dormant during the financial year, you are still required to file a tax return. However, the process is simplified:
- Simplified Filing: Complete only two essential fields using the “File Form C-S/C for Dormant Company” digital service at mytax.iras.gov.sg.
- Waiver Option: If your company has been granted a waiver to file the return, ensure that you adhere to the terms of the waiver.
Handling Losses and Carry-Forward Provisions
If your company incurred losses in the previous year, you might be eligible to carry forward these losses to offset future taxable income. Ensure accurate reporting in your tax computations to benefit from this provision.
Important: Tax Incentives to Know About
Specific tax incentives in Singapore can help reduce your overall contribution. Here are the most basic ones that most firms should know about:
Enhanced Tax Exemption for Startups
New startups, both local and foreign, can benefit from a tax exemption scheme that offers:
- 75% exemption on the first $10,000 of chargeable income.
- 50% exemption on the next $290,000 of chargeable income.
This scheme is available for the first three consecutive Years of Assessment (YAs).
Partial Tax Exemption for All Companies
Beyond the startup phase, all companies in Singapore can enjoy a partial tax exemption, which includes:
- 75% exemption on the first $10,000 of chargeable income.
- 50% exemption on the next $290,000 of chargeable income.
These exemptions are also available to companies limited by guarantee.
Corporate Income Tax Rebate and Cash Grant
The Singapore government provides:
- A Corporate Income Tax (CIT) Rebate of up to 40% of tax payable, capped at $40,000.
- A CIT Rebate Cash Grant for companies that hire local employees, which can further reduce tax liabilities.
Double Tax Deduction for Internationalisation
Companies expanding overseas can claim a double tax deduction on qualifying expenses for international market expansion and investment development:
- Market research and promotional activities.
- Overseas business development trips.
This scheme is available until 31 December 2030.
Research & Development (R&D) Tax Measures
Singaporean companies can claim an additional 150% tax deduction on qualifying R&D expenditure, supporting innovation. This includes:
- Staff costs and consumables related to R&D projects performed in Singapore.
Examples of qualifying R&D costs include STEM staff costs, chemicals and prototypes used in product development, and equipment and tools for research.
How to Get Help?
For more detailed information and updates, visit the official IRAS website. You can also explore the list of the best company tax preparation services in Singapore.
