bill.com

Create a BILL developer account via the sandbox sign-up guide or production sign-up form. In the BILL web app, generate a developer key as an ADMINISTRATOR; the guide notes you can generate developer keys in the web app and use them with your test organizations and users.

Create a BILL developer account following the sandbox sign-up guide. Your sign-up creates the username (email), password, and organization ID required for API login. Complete the web signup and 2-step verification, then use the resulting account credentials for API sign-in.

Sign in to the BILL sandbox web app, then go to Settings → Sync & Integrations → Tokens, click NEW, set a token name, and save. The token name becomes the API login userName and the generated token value becomes the API login password for sync-token sign-in.

Generate a Console API token following the Accountant Console operations flow referenced from BILL keys & tokens. BILL documents that this token is used with POST /v3/login together with your BILL username, organization ID, and developer key to access client organizations for AP and AR operations.

For sandbox, submit the Sandbox Access Form described in Authentication with Spend & Expense API token; BILL provides an apiToken for the test company. For production, follow Generate an API token in BILL Spend & Expense. BILL notes only ADMIN users can generate production Spend & Expense API tokens.