Your company closed its books on 31 December 2026 with S$1,200,000 in revenue. In February, a reminder about ECI arrives. You have filed no tax return yet, so you wonder why IRAS wants a number now.
ECI stands for Estimated Chargeable Income. You tell IRAS how much taxable profit you expect for the year. IRAS uses your estimate to start your tax bill early. You still file Form C-S or Form C later, and the final figure replaces your estimate.
When you must file
Generally, every company files ECI within 3 months from its financial year end. A company with a 31 December year end files by 31 March. A company with a 30 June year end files by 30 September. Your deadline follows your year end, not the calendar year.
Form C-S and Form C stay due on 30 November each year. ECI comes first.
When you do not need to file
Two conditions must both hold. Your annual revenue is S$5 million or less, and your ECI is nil. A company in this group does not contact IRAS, even when myTax shows Ready to File. If your company earns taxable profit, you file.
What goes into your estimate
Start with the accounting profit from your management accounts. Add back costs the tax law does not allow, such as private spending. Deduct capital allowances and other tax reliefs you claim. You do not wait for the audit to finish. An estimate is an estimate.
Worked example
Your year end is 31 December 2026 and you estimate chargeable income at S$180,000. Your company is not a new start-up, so partial tax exemption applies.
- Tax before exemption: 17% x S$180,000 = S$30,600
- Exempt on the first S$10,000: 75% x S$10,000 = S$7,500
- Exempt on the next S$170,000: 50% x S$170,000 = S$85,000
- Total exempt amount: S$7,500 + S$85,000 = S$92,500
- Chargeable income after exemption: S$180,000 – S$92,500 = S$87,500
- Tax on your estimate: 17% x S$87,500 = S$14,875
Rebates and cash grants change the final bill, and amounts differ by year of assessment. Check the current figures before you plan your cash.
Three mistakes to avoid
- You file a nil estimate because the audit is unfinished, while your management accounts show profit.
- You miss the 3-month deadline because your accountant waits for a full set of accounts.
- You skip cash planning. Your tax bill follows your ECI, so set money aside from the month you file.
Our corporate tax service prepares your ECI from your management accounts and handles Form C-S or Form C at year end: https://www.cschow.com.sg/corporate-tax-singapore/
This article gives general guidance. Your facts decide your filing position. Send your year end date and your latest management accounts, and I will tell you your ECI deadline.
WhatsApp +65 9876 3553
Email henry@cschow.com.sg
Henry Chow, Public Accountant, C S Chow & Co