> For the complete documentation index, see [llms.txt](https://docs.developer.singpass.gov.sg/docs/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.developer.singpass.gov.sg/docs/singpass-developer-docs/corppass-and-myinfo-business/technical-specifications/corppass-authorization-api-fapi-2.0.md).

# Corppass Authorization API (FAPI 2.0)

{% hint style="info" %}
**Integrate with FAPI 2.0 for Enhanced Security**

FAPI 2.0 is a high-assurance security profile built on OAuth 2.0 and OpenID Connect, that strengthens authentication and authorisation.

\
**What this means for partners integrating with Corppass Login**

* New services must use FAPI 2.0 to meet the latest security standards.
* All existing services onboarded before 23 March 2026 must migrate to FAPI 2.0 by 31 March 2027, as the legacy security profile will be deprecated on 1 April 2027. To ensure continuity of service, we encourage planning and completing migration early. [Refer to migration guide](/docs/singpass-developer-docs/corppass-and-myinfo-business/technical-specifications/corppass-authorization-api-fapi-2.0/migration-guides/migration-guide-legacy-to-fapi-2.0.md)
* Submit your migration plan (current progress and target date) so we can support your transition and avoid service disruption. [Submit migration plan](https://go.gov.sg/cp-fapi-migration-plan)

\
**What this means for partners integrating with Myinfo Business**

* Myinfo Business (v3) is now available for onboarding. [Refer to getting started guide](/docs/singpass-developer-docs/corppass-and-myinfo-business/products/myinfo-business/getting-started.md)
* All existing applications (v1/v2) must migrate to Myinfo Business v3 by 31 May 2027, as legacy versions will be deprecated after this date. To ensure continuity of service, we encourage planning and completing your migration early. [Refer to migration guide](/docs/singpass-developer-docs/corppass-and-myinfo-business/technical-specifications/corppass-authorization-api-fapi-2.0/migration-guides/migration-guide-myinfo-business-v1-v2-to-v3-fapi-2.0.md)
  {% endhint %}

## Introduction

This technical specification describes the **web-based Application Programming Interfaces (APIs)** provided by *Corppass* for use by *Relying Parties (RPs)*.

It defines the required endpoints and interactions to:

* Initiate user authentication using the **OpenID Connect (OIDC)** protocol
* Securely and reliably retrieve **identity** and **authorization information**

Corppass implements the **OpenID Foundation’s Financial-grade API (FAPI) 2.0 Security Profile**, a high-assurance security standard built on top of OAuth 2.0 and OpenID Connect.

This ensures that all authentication and authorization flows are protected using:

* **JWE-encrypted ID tokens**
* **JWT-based client authentication** (client assertions)
* **Sender-constrained access tokens via DPoP** (Demonstration of Proof of Possession)

## Getting Started

Follow the [Integration Guide](/docs/singpass-developer-docs/corppass-and-myinfo-business/technical-specifications/corppass-authorization-api-fapi-2.0/integration-guide.md) for step-by-step instructions on registering your application and implementing the secure authorization flow.

For existing partners moving from the Legacy Security Profile, please refer to the [Migration Guide](/docs/singpass-developer-docs/corppass-and-myinfo-business/technical-specifications/corppass-authorization-api-fapi-2.0/migration-guides/migration-guide-legacy-to-fapi-2.0.md) for specific transition steps.


---

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