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Onboard Now

Onboarding Steps for Software Developers

Step 1: Create and Setup your APEX account (one-time only)

Complete pre-onboarding steps to set up CorpPass assignments within your company.
Log into API Developer Portal and check your profile and Organization (cp_<uen>) is created.
Register Application.
Generate Secret Keys.

Step 2: Subscribe to the CPFB, IRAS and MOM APIs in Sandbox

Contact one_stop_payroll@iras.gov.sg to authorize your Organization to the Sandbox APIs.

Step 3: Complete the APEX Sandbox Connectivity Testing

Log into API Developer Portal, ensure that your OAuth 2.1 profile is set up with the necessary JWKS endpoint, and that your API key is set up. Check that your Organization is subscribed to the OAuth2.1 protected Sandbox APIs.
Ensure that you are able to curl to https://sandbox.api.gov.sg/oauth/cp/v2 and that you get HTTP error 403.

Step 4: Complete the CPFB, IRAS and MOM API Testing in Sandbox

Check that the Sandbox CPF/IRAS/MOM API is listed in Approved APIs, and download the specs to consume it.
Ensure that the necessary headers are included in the Sandbox API.

Step 5: Complete the APEX Production Connectivity Testing

Log into API Developer Portal, ensure that your OAuth 2.1 profile is set up with the necessary JWKS endpoint, and that your API key is set up. Check that your Organization is subscribed to the OAuth2.1 protected Production APIs.
Ensure that you are able to curl to https://public.api.gov.sg/oauth/cp/v2 and that you get HTTP error 403.

Step 6: Subscribe to the CPFB/IRAS/MOM APIs in Production

Contact one_stop_payroll@iras.gov.sg to authorize your Organization to the Production APIs.

Related Resources: Onboarding Guides