Retrieve an Access Token

Retrieve an OAuth 2 Access Token.

There are two ways of accessing the child companies:

1. Client Credentials Grant with a enterprise.child_companies_access scope and a custom header X_EASYSHIP_COMPANY_ID in each request to our Public API.
2. A custom Delegated Account Grant, that will generate access and refresh tokens associated with a specific child company defined in the easyship_company_id.