A company tax return goes smoothly when the paper is ready early. Work through these steps in order. They apply to every Singapore company, whatever the year end.
1. Find your Year of Assessment (YA)
The YA follows your financial year. A year ended 31 December 2025 belongs to YA2026. A year ended 30 June 2026 belongs to YA2027.
2. Gather your documents
– Financial statements and the trial balance
– The general ledger and bank statements for the year
– A fixed asset list with invoices for purchases and disposals
– Donation receipts
– A staff medical cost breakdown, because the deduction has a cap
– Last year’s tax computation and any unused items brought forward
– Payroll and CPF records
3. File your Estimated Chargeable Income (ECI)
ECI is due within 3 months after your year end. You skip the filing when annual revenue is S$5 million or less and your ECI is nil for the YA.
4. Pick the right form
– Form C-S (Lite) is optional. Use this form when your revenue is S$200,000 or less and you meet every C-S condition.
– Form C-S fits a Singapore-incorporated company with revenue of S$5 million or below and only 17%-taxed income. You make no carry-back, group relief, investment allowance or foreign tax credit claim. For YA2026 a company above S$5 million still uses C-S by concession, but moves to Form C for YA2027 if revenue stays above S$5 million.
– Form C covers everything else, including foreign-incorporated companies and Singapore branches.
– A dormant company files the Form for Dormant Company by 30 November. A dormant company still files its ACRA annual return.
5. Set up Corppass access
You file on the myTax Portal. Each staff member or agent needs Corppass authorisation for “Corporate Tax (Filing and Applications)”. Your Corppass administrator grants this, so ask well before the deadline.
6. File by 30 November
The deadline is 30 November of the YA. For YA2026 this is 30 November 2026. IRAS announced a 15 December extension for e-filers in an earlier release, but plan for 30 November.
7. Pay what IRAS assesses
Your Notice of Assessment shows the tax payable and the payment date. For YA2026 the rebate is 50% of tax payable, capped at S$40,000. Active companies with at least one local employee in 2025 also receive a minimum S$2,000 cash grant.
Two companies, two timelines
– Company A has a 31 December 2025 year end. ECI was due 31 March 2026. The return is due 30 November 2026.
– Company B has a 30 June 2026 year end. ECI is due 30 September 2026. The return is due 30 November 2027.
The ECI date moves with your year end. The return date stays on 30 November.
What happens when you do not file
IRAS offers composition of up to S$5,000, issues a court summons, or raises an estimated assessment, payable within 1 month of the Notice of Assessment. After 2 or more years without filing, the penalty is twice the assessed tax plus a fine of up to S$5,000.
Keep all records for at least 5 years.
Send me your documents early. Send your latest profit figure or your question by WhatsApp to +65 9876 3553 or by email to henry@cschow.com.sg.
Henry Chow
Public Accountant, C S Chow & Co