> 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

> For clean Markdown of any page, append .md to the page URL.
> For a complete documentation index, see https://avalara.ferndocs.com/llms.txt.
> For AI client integration (Claude Code, Cursor, etc.), connect to the MCP server at https://avalara.ferndocs.com/_mcp/server.

# Q-and-A

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.

> **Note**
>
> Part of the **1099 & W-9** integration guide. [Open the full "Q-and-A" milestone on Avalara](https://developer.avalara.com/products/avalara-1099-and-w9/integration-guides/1099-and-w-9/vly2542886249530/) to see every page in this section.