Form C, C-S and C-S Lite filing — Costs and fees breakdown

Form C, Form C-S and Form C-S (Lite) are the three corporate income tax return options in Singapore, and professional preparation costs range from around S$400 for a simple C-S (Lite) filing to S$2,000 or more for a full Form C with supporting schedules. This guide explains which form applies, the thresholds, and the fees and deadlines involved.

What Form C, C-S and C-S (Lite) are

These are the corporate income tax returns filed with the Inland Revenue Authority of Singapore (IRAS). Form C-S is a simplified return for smaller qualifying companies, Form C-S (Lite) is an even more streamlined version for the smallest companies, and Form C is the full return for companies that do not qualify for the simplified forms. Section 62 of the Income Tax Act 1947 requires companies to make a return of income each year, and the correct form depends on revenue and the nature of the company’s affairs. Filing guidance is published by IRAS.

Who files which form

A company can file Form C-S if its annual revenue is S$5,000,000 or below and it meets the qualifying conditions, including deriving only income taxable at the prevailing corporate rate and making no claims for specified reliefs. Form C-S (Lite) is available where annual revenue is S$200,000 or below and the same qualifying conditions are met. All other companies file Form C with full financial statements and tax computation. Companies claiming specific reliefs cannot use the simplified forms; see our note on the Section 37O M&A allowance for one such relief.

Cost and fee breakdown (2026)

Professional fees in 2026 commonly run: Form C-S (Lite) S$400 to S$700; Form C-S S$600 to S$1,200; and Form C S$1,200 to S$2,500 or more where schedules, capital allowances and adjustments are complex. Estimated Chargeable Income (ECI) preparation adds S$150 to S$400. These fees assume the bookkeeping and financial statements are already complete.

Timelines and thresholds

ECI must be filed within three months of the financial year end unless the company qualifies for the filing waiver, available where annual revenue is not more than S$5,000,000 and ECI is nil. The corporate income tax return, whichever form applies, must be filed by 30 November each Year of Assessment. The prevailing corporate income tax rate is 17 per cent, with partial tax exemption reducing the effective rate for smaller companies.

Step-by-step: filing the return

First, complete the financial statements. Second, prepare the tax computation, adjusting accounting profit for non-deductible expenses and capital allowances. Third, determine the correct form using the revenue thresholds. Fourth, file ECI within three months of year end. Fifth, file Form C, C-S or C-S (Lite) through myTax Portal by 30 November. Our companion guide, the complete Form C, C-S and C-S Lite filing guide, walks through the portal screens. Accounting inputs should follow SFRS.

Common mistakes and gotchas

Frequent errors include filing Form C-S when revenue exceeds S$5,000,000, missing the ECI deadline, omitting capital allowance claims, and failing to add back non-deductible expenses. If you are expanding headcount alongside growth, foreign founder hiring is covered in the EntrePass founders walkthrough.

Documents and information you will need

Accurate output depends on complete source records: bank statements for every account, sales invoices, purchase invoices and receipts, payroll records, loan and lease agreements, and fixed-asset registers. For GST-registered businesses, tax invoices must meet IRAS content requirements. The opening balances from the prior year’s financial statements must reconcile. Providing these promptly each period is the single biggest driver of lower fees and faster turnaround.

Consequences of getting it wrong

Inaccurate books lead to wrong GST returns and understated or overstated tax, both of which expose the company to IRAS penalties and interest. Poor records can invalidate the audit-exemption position and complicate financing. Directors remain responsible under the Companies Act 1967 for keeping proper records, so weak bookkeeping is ultimately a governance risk, not merely an administrative one.

How we can help

Raffles Corporate Services handles the full lifecycle described above: gathering the documents, meeting the deadlines, and coordinating with the relevant authority so nothing falls through the cracks. We work with a panel of corporate and employment law firms where formal legal advice is needed, and we keep fees transparent and fixed where possible so you can budget with confidence. Engaging early, before deadlines loom, is consistently the cheapest path.

FAQs

Which form should my company file? C-S (Lite) if revenue is S$200,000 or below, C-S if S$5,000,000 or below with qualifying conditions, otherwise Form C.

When is the filing deadline? 30 November of the Year of Assessment for the income tax return, and within three months of year end for ECI.

What does filing cost? From about S$400 for C-S (Lite) to S$2,500 or more for a complex Form C.

What is the corporate tax rate? 17 per cent, reduced in effect for smaller companies by partial tax exemption.

Need help with this? Call, SMS or WhatsApp +65 8501 7133, or email [email protected]. Raffles Corporate Services works with a panel of corporate and employment law firms; this article is general information, not legal advice.