This page is for Documentation, version Integration guides (default).
For other versions, use one of these documentation indexes:
- Integration guides (default): https://avalara.ferndocs.com/docs/integration-guides/llms.txt
- Refactor guides: https://avalara.ferndocs.com/docs/refactor-guides/llms.txt
- Get certified: https://avalara.ferndocs.com/docs/get-certified/llms.txt
- Agent to Agent (A2A): https://avalara.ferndocs.com/docs/agent-to-agent-a2a/llms.txt
- AI use cases: https://avalara.ferndocs.com/docs/ai-use-cases/llms.txt
- API versioning: https://avalara.ferndocs.com/docs/api-versioning/llms.txt
Guide: 1099 & W-9
Learn about the authentication method used by the Avalara 1099 & W-9 API.
The Avalara 1099 & W-9 API uses OAuth 2.0 Bearer Token Authentication. You authenticate by generating a bearer token using your Account ID and License Key. Then include that token in the Authorization header of your API requests.
