GST API Frequently Asked Questions.

GST API Frequently Asked Questions.

With regard to the SingPass session, will the system accept chunks of data which are sent over different SingPass sessions (e.g. timeout)

  1. The SingPass token is validated at the start of the transmission. 
  2.   Should the token expire during the transmission, the system should still accept the submission if they contain the same identifier and fulfil all other requirements and checks. 
  3. The system will also accept chunks of data sent over different SingPass sessions (e.g. re-login), if they contain the same identifier and all requirements are met.

The taxpayer made a successful submission for both F5 and transaction listings via the accounting software but needed to make an adjustment to the return. Will he have to resubmit the transaction listings?

  • Taxpayer has to submit a GST F7 return via myTax Portal to rectify errors made in the submitted GST F5 return. 
  • If the amendments to the GST return results in changes to the transaction listings, the taxpayer has to resubmit the entire transaction listing using a new identifier.

    • If GST F5 and transaction listings are submitted together, but the submission of transaction listings failed, is there a need to resubmit both? 

    1. Software should only re-transmit the transaction listing. 
    2. If an amendment had to be made to the GST F5 due to changes in the transaction listings, taxpayer should proceed to file a GST F7 via myTax Portal.

    General Ledger (GL) listings were required as part of the IAF file transmission. However, there is no such requirement in the API specifications. Is this correct? 

    1. There is no need to submit GL listings via API.
    2. IRAS only requires the company information, purchase and supply tables

    Is there any way for the taxpayer to check whether the GST F5 return and transaction listings were successfully submitted to IRAS? (e.g. a service to perform a search using the identifier) As this is a new initiative, the taxpayer might wish to verify what was sent from the software against what was received by IRAS. 

    1. IRAS will not be providing a service for taxpayers to perform such reconciliation of records. 
    2. It is up to the software developer to build relevant archival features into the software to enable such checks. 
    3. Note: Currently, taxpayers can retrieve a copy of their submitted GST F5 return via myTax Portal.


    In the current e-service on myTax Portal, there will be a prompt to indicate that a GST F5 is already submitted. Is this the same user experience for the API mode of submission? 

    1. If the company attempts a resubmission of GST F5 via the accounting software, there will be an error response returned to indicate that a submission had already been received.
    2. We recommend that the software be designed to include a prompt, with an appropriate message, to inform the taxpayer that a submission had been received and duplicate submissions are not allowed.

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