Tips on e-Filing Form C

Getting your Access Code and authorising an "Approver" for "Corporate Tax Matters" beforehand, and other useful tips on e-Filing Form C.

Before e-Filing Form C

Important Notes:

  1. Ensure that you have been duly authorised by the company as an "Approver" for "Corporate Tax Matters" via the e-Services Authorisation System (EASY).
  2. Ensure that you have the company's tax reference number and your personal SingPass or IRAS PIN.
  3. Download and install Adobe Reader XI (i.e. Version 11) or higher for Form C (Upload).
  4. Uncheck the security setting of Adobe Reader if you are unable to open the Form C (Upload) after installing the Adobe Reader XI (i.e. Version 11) or higher. Refer to FAQ 41 for instructions.
  5. Set aside at least 30 minutes to complete this electronic tax return.
  6. Get ready the following documents in softcopy for submission to IRAS:
     Type of DocumentsWho needs to submit? Maximum file size 
     Form C (Upload)For companies who are using Form C (Upload) to e-File 4MB 

    Audited/ Unaudited financial statements

    • The financial statements (including notes to the financial statements), prepared in compliance with the Companies Act, must be accompanied by the Directors' Report and Statement by Directors.

    (1)Please refer to ACRA's website on how to prepare your financial statements in XBRL format.
    (2)A dormant company is one which did not carry on business and had no income in the basis period.

    All companies, except

    • those that have filed a full set of financial accounts with ACRA in XBRL format(1); or
    • those which are dormant(2)
    Detailed profit and loss statement. This can be filed together with either the audited/ unaudited financial statements or tax computation and supporting schedules.All companies, except those which are dormant  NA

    Tax computation and supporting schedules

    All companies, except those which are dormant4MB 

    Revised tax computation(s) for prior Year(s) of Assessment (YAs)

    • Example: Company claims current year Capital Allowances/ Losses against assessable income of the immediate preceding YA and submits a revised tax computation for the immediate preceding YA
    Only companies submitting revised tax computation(s) 4MB 
    Research & Development (R&D) Claim FormOnly companies claiming tax benefits on R&D expenditure 2MB 
    Declaration Form for the purpose of claiming Writing-Down Allowances for Intellectual Property Rights (IPRs) under Section 19B of the Income Tax ActOnly companies claiming Writing Down Allowances for IPRs 




  7. Ensure that the softcopy documents are in pdf format. If not, convert them to pdf file format using software convertor (e.g. PrimoPDF).
  8. Ensure that the hardcopy documents are scanned into pdf files and the images are clear.
  9. Use font size of at least 11 for your attachments.
  10. Choose the recommended resolution of 100dpi black and white if you need to reduce file size of attachments.

e-File Form C in 4 Simple Steps

  1. Request a new Access Code by downloading the application form if:
    • Your company does not have an Access Code;
    • Its existing Access Code is no longer valid.
  2. Complete and submit the form to IRAS via fax or email.

You may skip this step if you already know your company's Access Code.

You need to authorise yourself/ a third party as an "Approver" for "Corporate Tax Matters" before you/ the third party can e-File.

  1. Log in to the e-Services Authorisation System (EASY) using your company's Access Code.
  2. Authorise yourself/ a third party as an "Approver" for "Corporate Tax Matters" and log out.

You may skip this step if you have already authorised yourself or a third party as an "Approver".

  1. Log in to
  2. Select Organisation/ Business Tax Matters and choose either SingPass or IRAS PIN login.
  3. Key in your personal SingPass or IRAS PIN, followed by your Organisation Tax Ref No.
  1. Click on Corporate Tax and select File Form C-S/ C.
  2. Select the Year of Assessment you are filing, followed by Form Type:

    Online Form C
    • Complete the Form
    • Click to Confirmation Page to verify that the information declared is correct. Thereafter, complete the Declaration and fill in Details of Filer & Contact Person.
    • Click on Submit Document to upload the relevant documents.
    Form C (Upload)
    • Complete the Form C (Upload). No signature is required in Part V Declaration.
    • Save the duly completed Form C (Upload) in your local drive and upload the file and the relevant documents to myTax Portal. Do not upload a scanned or printed copy of Form C or Form C-S.
  3. Click on Submit to IRAS.
  4. You will receive an instant acknowledgement upon successful filing.

Points to Note when e-Filing

Filing Deadline

Your company enjoys the extended filing due date of 15 Dec, instead of 30 Nov when you e-File Form C.

Online Help

For guidance on how to complete Form C, please:

  • Click on the iHelp icon < i2 >; or
  • Click on " Ask IRAS" at the top of the page.

Save Draft Facility

If you are not able to complete your filing in one session, please save the Form C as 'draft'. The draft will be retained in the portal up to 15 Dec. You can access the draft anytime till 15 Dec and make the necessary amendments before you submit your Form C.


Please do not leave your filing session idle for more than 20 minutes. Otherwise, the session will expire and you will be required to log in to the portal again. If you are unable to complete your filing in one sitting, do remember to save a draft of your filing before you log out from

New Companies Filing First Tax Return

If your company's first set of financial statements covers a period of more than 12 months from its date of incorporation, please indicate the relevant financial period under General Info.

In the subsequent pages, you will need to:

  • Attribute the company's adjusted profit/ losses to two Years of Assessment (YAs)* (i.e. YA 2016 and YA 2017); and
  • Complete the fields required for two YAs in the Form C. This is because the basis period for each YA should generally not exceed 12 months.

* Time apportionment basis may be used if the company is unable to directly identify the adjusted profit/ losses before other deductions to the corresponding basis period for each YA.

For more information on YA and basis period for new companies, please refer to Attribution of Profits/ Losses for New Companies.

Acknowledgement of Successful e-Filing

Upon successful e-Filing, you will receive an instant acknowledgement of receipt. The same acknowledgement will also be available at under the "View Corporate Tax Notices" e-Service.

Detailed Information on Completing Form C

User Guides

Detailed user guides for Online Form C:

Detailed user guides for Form C (Upload):

Frequently Asked Questions FAQs

For more details on e-Filing of Form C, please refer to our FAQs (280KB).

Contact Us

Please contact us if you need assistance or clarification on Form C e-Filing:

  • Email us via myTax Mail
  • IRAS Helpline: 1800-356 8622 (8 a.m. to 5 p.m. from Mon to Fri)


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