It is mandatory for newly incorporated Singapore companies that have  income or profits derived from within Singapore or outside of Singapore  to declare its income through an Income Tax Form for companies (Form C)  each calendar year. The due date for companies to submit its  accomplished Form C – together with its accounts, tax computations and  other supporting records – is by the 31st of October each year.

However, a newly incorporated company has to submit its first set of Form C to IRAS on the financial year end of that company.