If you wish to revise the amount declared in the form and/or submit a revised tax computation after you have filed Form C/ Form C-S, you can do so electronically via myTax Portal under “Object/Revise Assessment” if you have been authorised as an "Approver" for "Corporate tax matters" via EASY. When submitting your revision(s) to Form C-S, please attach the financial accounts, revised tax computation and supporting schedules.
For more details on e-Service “Object/Revise Assessment”, please refer to:
For companies (340KB)
For tax agent (360KB)
Alternatively, you may complete the Form for Filing Revised Income Tax Computation(s) (160KB) and submit it together with your revised tax computation where applicable. For more details, please refer to Submission of Revised Income Tax Computations by Companies.