flatin.pt MCP server — Portuguese property taxes

An MCP server that answers the questions people ask before buying a home in Portugal: how much IMT and stamp duty on top of the price, and what yearly IMI rate a municipality sets — for all 308 municipalities, with the source and the year of every number.

It is run by flatin.pt and listed in the official MCP Registry as pt.flatin/property-taxes.

You:    I'm buying a flat in Matosinhos for 280 000 €. What do I pay on top, and what's the IMI there?

Claude: [imt_calculate value="280000"]  [imi_rate municipality="Matosinhos"]
        IMT 9 142,04 €, stamp duty 2 240,00 €, deed and registration about 900 € —
        12 282,04 € on top of the price.
        IMI in Matosinhos (Porto): 0,37 % a year on the taxable value (VPT), 2025 table.
        Source: Autoridade Tributária tables, computed by flatin.pt.

Tools

Tool	What it answers
imt_calculate	What a purchase costs on top of the price: IMT (transfer tax), Imposto do Selo (stamp duty) and an estimate for the deed and registration. Official 2026 tables, including the reduced scale for buyers aged 35 or under.
imi_rate	The yearly property tax (IMI) rate of one municipality, by name or four-digit code, with its history since 2023. Where a municipality sets no single rate (it is set per parish), the answer says so instead of returning zero.
imi_annual_cost	Yearly IMI for an urban property with a given taxable value (VPT). VPT is the tax authority's valuation, not the purchase price.
request_consultation	How to reach a licensed real estate agency (AMI): the form link and the GDPR consent text in the user's language. The request is sent by the person, never on their behalf.

Every successful answer carries an attribution field — who computed it, from which table and year, and a link to the primary source. Please show it to the user: numbers without a source cannot be checked.

Connect

The server is remote — nothing to install. Point your client at:

https://flatin.pt/mcp

Claude Code

claude mcp add --transport http flatin https://flatin.pt/mcp

Clients that can only start a local process (stdio) — use the bridge in this repository. It needs Node.js 18.17 or newer and has no dependencies:

claude mcp add flatin -- npx -y github:flatinpt/mcp

{
  "mcpServers": {
    "flatin": {
      "command": "npx",
      "args": ["-y", "github:flatinpt/mcp"]
    }
  }
}

The bridge forwards each JSON-RPC message to https://flatin.pt/mcp and writes the answer back. It stores nothing and sends nothing except what your client sends. Set FLATIN_MCP_URL to point it elsewhere.

Docker

docker build -t flatin-mcp . && docker run -i --rm flatin-mcp

The data behind it

• IMI rates, all 308 municipalities, checked line by line against the Autoridade Tributária portal — open data page, CSV, licence CC BY 4.0.
• IMT and stamp duty from the official 2026 tables — the same numbers as the IMT calculator.
• REST API with the same functions: API and data · OpenAPI schema.

The MCP server, the API and the website call the same code, so the three never disagree by a cent.

Guides

• Buying property in Portugal: costs and taxes
• NIF and residency for foreign buyers
• In Portuguese: Comprar casa: custos e impostos · Calculadora de IMT

Development

node --test

This repository is published from the flatin.pt codebase; issues and suggestions are welcome here.

Licence

MIT — see LICENSE. The data returned by the server is licensed separately under CC BY 4.0.