Singapore Corporate Tax Filing Deadlines for YA 2025

Here’s a quick overview of the key deadlines every company should be aware of:

1. ECI Filing Deadline – Within 3 Months from Financial Year End

• All companies must file ECI within 3 months after the Financial Year End (FYE).
• For example, if your company’s FYE is 31 December 2024, the ECI deadline is 31 March 2025.
• Companies with annual revenue not exceeding S$5 million and zero ECI can be exempted from filing—but exemption must be confirmed on IRAS’s system.

2. Form C-S / C / C-S (Lite) Filing Deadline – 30 November 2025

• All companies are required to file the Income Tax Return (ITR) for the Year of Assessment 2025 by:
  • 30 November 2025 (e-Filing only; paper submissions are no longer accepted).
• The filing must be done regardless of whether your company was active, dormant, or not generating income in that year.

💡 Key Forms You Need to Know

Depending on the company’s structure and size, you will file one of the following:

🔹 Form C-S

• For companies with:
  • Annual revenue ≤ S$5 million
  • Only Singapore-sourced income
  • No claim for Group Relief, Carry-Back of Losses, or Investment Allowance

🔹 Form C-S (Lite)

• For small companies with:
  • Revenue ≤ S$200,000
  • Simple tax affairs

🔹 Form C

• For companies that do not qualify for Form C-S
• Requires submission of detailed tax computations, financial statements, and supporting schedules

🧾 Why Corporate Tax Filing Matters

Filing corporate tax on time is legally mandatory in Singapore. Failure to comply can result in:

• Late filing penalties (ranging from $200 to $1,000 or more)
• Estimated Notice of Assessment (NOA) issued by IRAS based on their assumptions
• Legal action for non-compliance
• Ineligibility for certain government grants or tax incentives

✅ How to File Corporate Tax in Singapore

Here’s a simplified step-by-step overview of the corporate tax filing process:

Step 1: Determine Your Financial Year End (FYE)

This sets the timeline for your ECI and ITR filing. Most companies choose 31 December as their FYE, but IRAS allows flexibility.

Step 2: File Estimated Chargeable Income (ECI)

• Login to myTax Portal using CorpPass
• File ECI within 3 months after FYE
• If ECI is nil and your revenue is under S$5 million, apply for exemption

Step 3: Prepare Your Tax Computation

• Compile your Profit & Loss Statement, Balance Sheet, and other financial documents
• Calculate taxable income after allowable deductions

Step 4: File Form C-S / C / C-S (Lite)

• Submit through IRAS’s myTax Portal
• Ensure all supporting documents are uploaded if required
• Use IRAS’s e-Services to validate and auto-calculate where possible

🚫 Common Mistakes to Avoid

Many businesses, especially startups or SMEs, make the following errors:

1. Missing the ECI deadline – Even if no tax is due, ECI must be filed unless exempted
2. Incorrect classification of income – Misreporting local vs. foreign income
3. Submitting wrong form type – Not all companies qualify for the simplified Form C-S
4. Not keeping adequate records – Financial statements must be retained for at least 5 years

💼 Can I Outsource Corporate Tax Filing?

Yes, many companies engage corporate service providers or accounting firms in Singapore to handle tax filings professionally.

Outsourcing tax filing can:

• Ensure timely and accurate submissions
• Minimise tax liability through proper planning
• Avoid penalties and IRAS audits
• Save internal resources and focus on growing your business

If you’re unsure about your tax obligations, it’s best to consult a qualified tax advisor or corporate secretary.

📣 Tips to Stay Compliant in 2025

• Set calendar reminders for ECI and Form C-S/C deadlines
• Maintain clean and updated bookkeeping throughout the year
• Review IRAS guidelines regularly as policies may change
• Consider e-filing early to avoid last-minute issues
• Always double-check form type before submission

📍Final Thoughts

Understanding and adhering to the corporate tax filing deadlines in Singapore is crucial for business compliance and long-term success. With the ECI filing due within 3 months of FYE, and the Income Tax Return due by 30 November 2025, it’s time to plan ahead.

Whether you’re a newly incorporated startup or a seasoned SME, don’t let tax deadlines catch you off guard. Stay proactive, stay informed, and stay compliant.

💬 Need Help With Your Corporate Tax Filing?

At Think SME, we help businesses like yours navigate tax filing, accounting, and compliance effortlessly. Let us handle your deadlines while you focus on growing your business.

👉 Contact us today to find out how we can simplify your corporate tax obligations.