Upgrade Procedure: Deprecation of the Login Method in the REST API

To work with data in MYOB Acumatica through the REST API, an external application needs to get access to the system in one of the following ways:

• Directly sign in to MYOB Acumatica with a username and password by using the Login method
• Implement the OAuth 2.0 or OpenID Connect (OIDC) mechanism of authorization

Authentication with only a username and password is less secure than authorization through OAuth 2.0 or OIDC. To provide greater security of user data, the direct sign-in method will be deprecated as follows:

• In MYOB Acumatica 2026.1.1, the Login method is marked as obsolete.
• In a future version of MYOB Acumatica, the Login method will be removed.

We recommend updating your application to use the OAuth 2.0 or OIDC mechanism of authorization instead of the Login method. For details about OAuth 2.0 and OIDC, see Authorizing Client Applications to Work with MYOB Acumatica.