Corporate Tax in Singapore: What Companies and Startups Need to Know
For many businesses in Singapore, the end of the financial year falls on 31 December. That makes Q4 the perfect time to review your company’s tax position and ensure you're ready for filing season.
Singapore is known for its low and business-friendly tax regime, but corporate tax in Singapore still comes with compliance requirements and strict deadlines. Whether you're an established company or one of the many startups in Singapore, understanding the fundamentals can help you avoid costly errors and unlock valuable exemptions.
This article breaks down the essentials of corporate tax in clear terms (with official resources linked) and explains how CSLB Asia supports companies to stay compliant, efficient and confident through every stage of the tax process.
And if you are looking at setting up a company in Singapore then our 90-Day Blueprint is for you.
Corporate Tax in Singapore
Corporate tax in Singapore is a flat 17% rate on chargeable income. That is taxable income after deducting allowable expenses and exemptions. The system is based on territorial taxation, meaning that only income sourced in Singapore, or foreign income remitted into Singapore, is taxable.
There is no capital gains tax on corporate profits from the sale of assets and dividends paid to shareholders are also not taxed. These features make Singapore an attractive base for companies looking to scale efficiently and reinvest profits.
Companies are taxed on a preceding-year basis. If your financial year ended on 31 December 2025, the corporate income tax return (Form C-S/C) must be submitted by 30 November 2026.
The IRAS have a clear guide to Corporate Income Tax you can review here.
Tax Reliefs and Exemptions for Startups and SMEs
Singapore has positioned itself as the leading business hub for Asia and its tax system reflects this ambition. To attract both local and foreign investment, especially in the startup and innovation sectors, the government offers generous tax incentives for new companies.
Understanding these exemptions can significantly reduce a company's effective tax rate, especially for startups in Singapore, and is a key step in making the most of Singapore’s pro-business environment.
Start-Up Tax Exemption Scheme (SUTE)
Qualifying new companies can receive:
75% exemption on the first SGD 100,000 of chargeable income
50% exemption on the next SGD 100,000
This applies for the first three Years of Assessment (YAs).
Partial Tax Exemption (PTE)
For all other companies:
75% exemption on the first SGD 10,000
50% on the next SGD 190,000
This means the first SGD 200,000 of chargeable income is significantly relieved from tax.
Deductible Expenses
Common deductible expenses include:
Employee salaries and CPF contributions
Office rent and utilities
Marketing costs
Professional fees (legal, accounting, advisory)
Depreciation (via capital allowances)
If you’re unsure what qualifies as a deductible business expense, IRAS provides a comprehensive guide outlining allowable deductions.
Navigating Singapore’s tax exemptions and allowable deductions can be more complex than it first appears. While the rules are clearly outlined, interpreting them correctly and applying them strategically requires a solid understanding of the full tax framework. Using a company for all your accounting services can be beneficial as many businesses miss out on savings simply because they don’t know what qualifies.
Our accounting services are specifically designed to ensure you are maximising legally available deduction and exemption. We help companies structure their finances for both compliance and tax efficiency so you stay on the right side of IRAS while making the most of Singapore’s pro-business incentives.
Corporate Tax Filing: Key Forms and Deadlines
All companies in Singapore must file an Estimated Chargeable Income (ECI) (a full guide about ECI here) and an annual corporate income tax return.
We find companies confuse Estimated Chargeable Income and annual tax filing. Filing ECI is not the same as filing the corporate income tax return. Both are mandatory for companies in Singapore. While they are separate submissions, both require a clear picture of the company’s financials and both are essential to staying compliant with IRAS.
Filing Timeline
Estimated Chargeable Income (ECI): Within 3 months of financial year end (if financial year end is 31 Dec 2025 then this is 31 March 2026)
Tax filing: Form C-S / C-S (Lite) / C: By 30 November of the following year
ECI Filing
This is a declaration of your company’s estimated taxable income. Even if the company expects no chargeable income, most companies still need to file unless exempted. Read more about the ECI filing requirements here.
Tax Filing: Form C-S / C-S (Lite) / C
These are the final tax forms used to declare your actual chargeable income.
Form C-S (Lite): For very small companies (revenue ≤ SGD 200,000)
Form C-S: For qualifying small companies
Form C: For all other companies (full return + financial statements)
The IRAS website has a comprehensive guide of filing.
Common Pitfalls with Tax Filing
While Singapore’s tax system is more straightforward than in many jurisdictions, we regularly see companies run into avoidable issues, especially when trying to manage everything in-house.
It’s worth noting that the system is designed to allow business owners to file their own ECI and corporate tax returns directly with IRAS, and for some businesses, that may be sufficient. However, we often see that DIY filings result in oversights that lead to penalties, missed reliefs or unnecessary audit exposure. This is why using a company that specialises in accounting services can help to avoid typical challenges.
Common mistakes we see clients’ encounter with tax filing include:
Missing the ECI deadline, triggering late penalties
Filing the wrong form (submitting Form C-S when Form C is required)
Misclassifying income or deductible expenses
Overlooking foreign-sourced income that becomes taxable under certain conditions
Poor or incomplete record-keeping that fails to support the numbers submitted to IRAS
For startups and SMEs, these mistakes are often due to unclear guidance or DIY bookkeeping. The errors are not always from negligence, they often stem from simply not knowing what to look for. That’s where expert oversight becomes so valuable.
Our clients avoid these issues by relying on our accounting services, designed to offer clarity and control throughout the tax year.
Staying Compliant
At CSLB Asia, we support founders, directors and finance teams with a comprehensive approach to tax filing and compliance. We works with established business and startups in Singapore and our services include:
Year-end financial statements
Preparation and filing of ECI
Corporate income tax return (Form C/C-S/C-S Lite)
IRAS correspondence and clarification
Strategic tax planning and advisory
Integration with payroll and HR
If you are feeling the pressure and know you need a better system for managing your company finances, book a free 15-minute discovery call to discuss your tax needs. Schedule time with one of our experts now.
We also specialise in helping foreign founders and regional startups navigate the full Singapore business lifecycle, from setup to tax structuring to scaling, as well as navigating the complexities of workpasses and managing payroll.
Corporate Tax in Singapore, Optimise Don’t Just Comply
Singapore’s corporate tax system is pro-business, with low rates and generous exemptions, especially for startups in Singapore. But success depends on proper planning, timely filing and knowing which reliefs apply to your company. Taking a strategic approach to tax and compliance can lead to more efficient operations, clearer financial visibility, and ultimately, a stronger business overall.