Sign in to your BILL partner account. In the response, your partner API session is created and a BILL-generated sessionId is available. Use the sessionId in all subsequent API calls to confirm that you are in a signed-in session.

You get additional permissions with a partner account sessionId.

• Create a child BILL organization with POST /v3/partner/organizations.
• Create a user for the child BILL organization with POST /v3/partner/users.
• Sign in to the created organization as the created user of that organization with /v3/partner/login-as-user. After signing in, you can perform organization-level BILL API operations, such as creating a bill or paying a vendor. All organization-level BILL API operations require a devKey and sessionId.

Note: When you create an organization and then create a user for that organization, it is important that you initiate risk verification with POST /v3/risk-verifications. See Initiate risk verification for an organization for more information.

You can sign out with POST /v3/logout. If your API session is inactive for 35 minutes, the session expires and you are automatically signed out.