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 44 (1.2MB) 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 
    Only companies claiming tax benefits on R&D expenditure 2MB 
    Declaration Form (901KB) 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 




    Form for reporting of related party transactions (1.29MB) New!

    Only companies with related party transactions and the value of such transactions disclosed in the audited financial statements for the financial period exceeds $15 million4MB 
  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 (105KB) 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.

For more detailed guides on e-Filing Form C:

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

Please click on the iHelp icon < i2> should you require on-the-spot guidance as you e-File the Form C.

Pre-filled Amounts

New! From YA 2018, to improve companies' e-Filing experience, the following amounts will be pre-filled:

  • Unutilised Capital Allowances brought forward
  • Unutilised Losses brought forward
  • Unutilised Donations brought forward
  • Current year Approved Donations
  • Unutilised Investment Allowances brought forward 

The amounts are pre-filled for the companies' easy reference. You are advised to verify the accuracy of the information. In case of any discrepancy with the details (i.e. the companies' carried forward amounts in their own records differ from the pre-filled records), you may update the pre-filled sections in the relevant Boxes under "Company's Declaration" (with the exception of donations).

The 250% deduction for donations is granted based on information obtained from the Institute of Public Characters (IPCs). You can view details of the current year approved donation amounts in the “View Donations” e-Service.

If the company has made an Approved Donation, but it is not reflected in the “View Donations” e-Service at, it may be due to:

  1. Differences in receipting date - The IPC may have recorded your donation in a later financial period and a deduction would be accorded in the corresponding YA.
  2. You did not provide your company's Unique Entity Number (UEN) to the IPC. Please update your donation record with the IPC and IRAS will amend your assessment when we receive the updated record.

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.


If you remain inactive on your local machine for more than 15 minutes, the system will prompt you to respond within 2 minutes. If there is still no activity within 2 minutes, you will be logged out of automatically.

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 2017 and YA 2018); 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 (1.06MB) Revised!.

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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