Documents to Prepare when Filing Form C-S/ C

Audited/ unaudited financial statements, tax computations, claim forms and other documents to prepare and/ or file with your Income Tax Return (Form C-S/ C).

Records and Accounts Keeping

Companies are required to keep proper records and accounts of business transactions. Using an accounting software helps business improve record keeping and comply with tax obligations. Business can also use the information captured in the software to ensure that operations are effective and efficient. The IRAS’ Accounting Software Register lists the accounting software that are able to meet IRAS’ technical requirements and businesses considering to use an accounting software for record keeping are encouraged to consider those in this list.

For companies eligible to file Form C-S

Companies that meet the qualifying conditions may report their income by filing Form C-S, instead of Form C.  Such companies must prepare:

The abovementioned documents are to be prepared and retained for submission upon IRAS' request, except for Declaration for the Purpose of Claiming Writing-Down Allowances for Intellectual Property Rights (IPRs) under Section 19B of the Income Tax Act (PDF, 901KB).

Companies claiming writing down allowances under Section 19B are required to submit the declaration form and valuation report (if applicable) to IRAS together with their Form C or Form C-S for the year of assessment relating to basis period in which the IPR was acquired. Companies are encouraged to use the e-Service Submit Document to submit the declaration form and valuation report. 

For companies not eligible to file Form C-S (i.e. it files Form C)

Companies that file Form C must prepare:

Such documents are to be submitted with Form C, unless it is specifically mentioned that such documents are to be retained and submitted to IRAS upon request.

More Details of such Documents

Audited/ Unaudited Financial Statements

For financial years starting on or after 1 Jul 2015, dormant companies and companies that meet the “small company” criteria(1) are not required to audit their financial statements. This is provided for under the Companies Act.

(1)  A company qualifies as a “small company” if:
• It is a private company for the financial year in question (i.e. it is owned by 50 members or less); and 
• It meets at least 2 of the following 3 quantitative criteria for immediate past two consecutive financial years:
 - total annual revenue ≤ $10m
 - total assets ≤ $10m
 - no. of employees ≤ 50

For a company which is part of a group to qualify for audit exemption:
a) the company must qualify as a small company; and
b) entire group must be a “small group”, i.e. the group must meet at least 2 of the 3 quantitative criteria on a consolidated basis for the immediate past two consecutive financial years.

Please refer to ACRA's website for more information on the Small Company Concept for Audit Exemption.

For financial years starting before 1 Jul 2015, dormant companies and exempt private companies with annual revenue of S$5 million or less are not required to audit their financial statements.

Companies that have filed a full set of financial statements with ACRA in XBRL format are not required to file the same with IRAS. Please refer to ACRA's website on how to prepare your financial statements in XBRL format.

Tax Computation

Tax computation and supporting schedules, including the following information:

Addition of New Assets
  • Description and purchase price of each asset. For motor vehicles, state the registration number of each vehicle.
  • Assets purchased on hire purchase terms: deposit and principal paid during the year for each asset.
  • Computation of capital allowances

Sale of Fixed Assets


Others documents include the following:

Statement of gross rental and direct expenses incurred on each property and state the rental period.

  • Jurisdiction in which foreign tax was paid;
  • Nature of the income;
  • Description of the services rendered, and whether the income was derived through a permanent establishment in the foreign jurisdiction and your basis for this claim, if applicable;
  • Name of the payer;
  • Date of withholding tax receipt/ voucher;
  • Gross amount of income, withholding tax rate and amount of tax withheld in foreign currency (include the corresponding S$ amount);
  • For a claim of DTR, the relevant Article of the Avoidance of Double Taxation Agreement under which the tax was withheld; and
  • Withholding tax receipt/ voucher*.

* If this is not available, a letter (XLSX, 10KB) certifying that foreign tax has been/ will be paid** on the income remitted may be submitted instead. The certification must be made by either a director/ auditor of the company, a public accountant in Singapore or a public accountant in the country in which the income was derived.

** IRAS may subsequently require the company to give confirmation of the amount of foreign tax paid after it has been paid.

For details, please refer to Double Taxation Relief (DTR) and Unilateral Tax Credit (UTC).

  1. Address of the property;
  2. Date of purchase and purchase price;
  3. Date of sale and sale price; and
  4. Name and address of the purchaser and whether the purchaser is related to the company, its directors or its shareholders. If so, state the nature of the relationship.
  1. A copy of the letter of offer from the Economic Development Board (EDB) or Building and Construction Authority (BCA);
  2. Details of qualifying capital expenditure incurred on the construction or renovation/ extension of the approved LIA building or structure and the computation of the Initial Allowance and Annual Allowance to be claimed;
  3. Copy of the verification form submitted to EDB or BCA previously in respect of the construction or renovation/ extension completed during the YA; and
  4. Certificate from a qualified quantity surveyor to certify the floor area used by another user where part of the approved LIA building or structure is used by another user.

For details, please refer to Land Intensification Allowance (LIA).

  1. For R&D activities outsourced directly by company to an overseas R&D organisation:
    1. Name and description of the intellectual properties arising from the outsourced R&D that are owned/ to be owned by the company in Singapore; and
    2. Brief description of the overseas R&D organisation (including the organisation's address).
  2. For R&D activities undertaken under a cost-sharing agreement:
    1. Name and description of the intellectual properties arising from the R&D under the cost sharing agreement; and
    2. A copy of the cost-sharing agreement.

For details, please refer to Deduction of Research & Development (R&D) Expenditure.

A company must maintain proper documentation of its R&D projects, so that it can substantiate its R&D claims to IRAS when requested. All documentation should be maintained from the start of the R&D project, rather than as an after-event. Some examples include test results, award of a patent resulting from R&D and press statements.  For more examples of information/ documentation that will help to substantiate R&D claims, please refer to our e-Tax guide, Research and Development Tax Measures (PDF, 1.22MB).

  1. An itemised list (including the related costs incurred) of the renovation or refurbishment works done to the business premises with addresses of the premises; and
  2. Confirmation on the itemised list that the renovation or refurbishment works do not require the approval of the Commissioner of Building Control.

For details, please refer to Deduction Claimed under Section 14Q for Expenditure on Renovation or Refurbishment Works.

Where the company claims a tax deduction for directors' fees:

  1. Date on which the director's fees were approved;
  2. Amount approved;
  3. Year in which any unapproved amount is written back (if applicable); and
  4. Amount (if any) of director's fees approved in arrears at the relevant Annual General Meeting (AGM) but the directors were entitled to the fees only after the accounting year in which such fees were approved.
  1. Confirmation by a responsible officer of the acquiring company that all qualifying conditions for M&A allowance have been met;
  2. Copy of the executed share purchase agreement and if such an agreement is not available, the instrument of transfer;
  3. Copy of the latest statement of financial statements of the target company (financial statements must be within 24 months from the date of agreement or transfer), whether the target company is incorporated in Singapore or outside Singapore; and
  4. Independent professional valuation report* of the ordinary shares of the target company acquired under any of the following circumstances:
    1. target company is incorporated outside Singapore;
    2. acquisition is funded by way of the acquiring company's issuance of shares/ units and the market value of such shares/ units is not readily available; or
    3. acquiring company does not wish to determine the M&A allowance based on the Net Asset Value (NAV) of its shares/ units.

* The requirement for an independent professional valuation report is waived when:

  1. the acquiring company and the shareholders in the target company are not related to each other on the date of share acquisition; and
  2. the value of the share acquisition is $5 million or below.

For details, please refer to Mergers and Acquisitions Allowance (Section 37L).

  1. Declaration that the foreign jurisdiction has exempted the specified foreign income from tax because of substantive business activities carried on by the company in that foreign jurisdiction; and
  2. Copy of the tax incentive certificate/ approval letter issued by the foreign jurisdiction. In the case of a foreign-sourced dividend, a dividend voucher (if available) stating that the dividend is exempt from tax due to the granting of a tax incentive to the payer company for carrying on substantive business activities in that foreign jurisdiction.

For details, please refer to Foreign Income Exempted from Tax as a Result of Incentive Granted by Foreign Jurisdiction ("Subject to tax" Concession).

  1. Brief description of the intellectual property;
  2. Country in which the intellectual property was registered;
  3. Name and tax reference number of joint-owners (if any);
  4. Breakdown of registration costs; and
  5. Confirmation that:
  1. The intellectual property is/ will be legally owned by the company; and
  2. The economic benefits from the exploitation of the intellectual property is/ will be accrued to the company.

For details, please refer to Costs of registering Intellectual Property Rights.

  1. Whether your company, the divesting company, is in the insurance business;
  2. Name of the investee company;
  3. Whether the investee company is in the business of trading Singapore immovable properties or principally carries on the activity of holding Singapore immovable properties (other than the business of property development).

    For non-listed shares disposed on or after 1 June 2022, whether the investee company:
    1. is in the business of trading immovable properties (situated in Singapore or elsewhere);
    2. principally carries on the activity of holding immovable properties (situated in Singapore or elsewhere); or
    3. has undertaken property development activities in Singapore or elsewhere. If so: (i) how the immovable properties developed are used by the investee company; and (ii) whether there have been property development activities carried out in the past 60 months prior to the disposal of shares by the divesting company;
  4. Dates of purchase and sale of the shares;
  5. Whether the shares sold are ordinary shares;
  6. How the gain was arrived at; and
  7. A copy of the documents showing that your company held at least 20% of the ordinary shares in the investee company for a continuous period of at least 24 months prior to the date of disposal of the shares.
  1. Date of approval letter from Enterprise Singapore or Singapore Tourism Board, if applicable;
  2. Details of event;
  3. Period of event;
  4. Claim amount per certificate, if applicable;
  5. Details of eligible expenses incurred; and
  6. Amount qualifying for further deductions.

Amount of gain or loss that is capital in nature.

  1. Details of debts (name and amount owing by each debtor) which were not incurred in respect of the trade or business, such as loans and advances;
  2. Details of debts which were taken over in the case of a transfer or merger of business;
  3. Details of debts in respect of a trade that had ceased, including any activity granted with pioneer incentive that had ceased;
  4. Segregation of debts relating to the different tax rate categories.

Where the amount of impairment loss exceeds $250,000 for trade debts owing by related parties, additional information is required:

  1. Relationship between the company and the trade debtor;
  2. Whether normal credit policy and terms were extended to the related party. If not, please provide the reasons for the extended credit policy and terms;
  3. Reasons the related party was unable to repay the trade debt; and
  4. Whether steps were taken to recover and enforce the debts. If not, please provide the reasons for not enforcing the debts.
  1. Registration number of and amount applicable to each vehicle; and
  2. Amount applicable to private cars and Q-plated cars registered on or after 1 Apr 1998.

For details, please refer to Motor Vehicle Expenses.

  1. Name of the company;
  2. Date of purchase and purchase price;
  3. Number of shares purchased;
  4. Reason(s) for the purchase; and
  5. Means of financing the purchase.

The documents below are required for each block of shares disposed:

  1. Name of the company;
  2. Date of purchase and purchase price;
  3. Date of sale and sale price;
  4. Number of shares purchased and sold;
  5. Reason(s) for the purchase and sale;
  6. Basis of arriving at the gain/ loss on disposal; and
  7. Reason(s) for treating the gain as not taxable or loss as deductible, if applicable.
  1. Address of the property;
  2. Date of purchase and purchase price;
  3. Name and address of the vendor and whether the vendor is related to the company, its directors or its shareholders. If so, state the nature of the relationship;
  4. Purpose of acquisition (e.g. for rental, resale);
  5. Use of the property since its acquisition and duration of each use. If the property was vacant at any point in time, please specify the period; and
  6. Means of financing the purchase.
  1. Vehicle registration books or cards of the existing and new vehicles;
  2. Certificate of Entitlement (COE) of the existing vehicle; and
  3. Approved De-registration Application Form for the de-registration of the existing vehicle.

Documents showing:

  1. Distributions passed on;
  2. Compensatory payments made; and
  3. Economic ownership remains with the transferor.

These documents should be prepared at the time of submission of the Corporate Income Tax Return. They should be retained by the company and submitted to IRAS only upon request.