The deadline for filing your Corporate Income Tax Return (Form C-S, Form C-S (Lite) or Form C) is 30 November each year. e-Filing via myTax Portal (mytax.iras.gov.sg) is compulsory for all companies – the older arrangement of 30 November for paper filing with an extended 15 December deadline for e-filers no longer applies.
Singapore taxes on a preceding-year basis, so the return filed in a Year of Assessment (YA) covers the financial year before it. For a financial year ended in 2025, the YA 2026 return is due by 30 November 2026.
There is a second, earlier deadline that companies often overlook: the Estimated Chargeable Income (ECI), which must be filed within three months of the financial year-end, unless your company qualifies for the filing waiver.
Filing is mandatory even if the company made a loss, was dormant, or had no business activity, unless IRAS has granted a waiver to file. Missing the deadline is an offence: IRAS may issue an estimated Notice of Assessment (payable even if overstated), impose a composition amount, and in persistent cases summon the company and its directors to court. Directors remain personally responsible even where filing is outsourced.
Apexia can prepare and file your ECI and Corporate Income Tax Return on time, and keep your tax computation and supporting schedules in order.