FinanzOnline and AI: Is there an MCP server for FinanzOnline?

FinanzOnline is the portal of the Austrian tax administration, run by the Federal Ministry of Finance (BMF). Companies and tax advisors submit returns there and read tax assessments. If you want an AI assistant such as Claude, ChatGPT or Microsoft Copilot to work with FinanzOnline, the first question is: is there an MCP server for it?

In short

We found no official MCP server from the BMF. The BMF offers SOAP web services, and a community server on GitHub builds on them: fon-api. It can submit returns, not only read.

What the BMF offers

Web services. On its page for software vendors (German), the BMF publishes the specifications for data transmission. For access, you create a separate user for “Webservices” in the FinanzOnline user administration. The sign-in to the session web service passes the participant ID, the user, the PIN and a vendor ID, according to the BMF the VAT number of the software vendor. The BMF adds that the setup is meant for specialists and that neither the BMF nor the FinanzOnline hotline helps with technical problems during the setup.

AI in the portal. On its sign-in page, FinanzOnline points to “Fred”, the chatbot of the tax administration, for questions. The BMF describes no connection of AI assistants to your own data.

What the community offers

fon-api is a Node.js package with an MCP server, created in June 2026. It builds and validates the XML files for returns and submits them through the file upload web service, for example U30, L1 or KA1. For a real submission it needs a registered vendor ID. It does not read tax assessments from the Databox; for that, the project points to another package.

What this means for an AI connection

With FinanzOnline, the question is not only whether it works technically, but what an assistant may do. A submitted return is a report to the tax administration. So:

• Let the assistant prepare data and check files, but not submit them itself.
• Use a separate web service user only for this purpose, so you can block it at any time.
• Review a community server yourself before you use it, or run your own.