n8n Workflow: Polish Contractor Due Diligence (VAT & KRS) AI

Verify Polish contractors fast: VAT & KRS due diligence with AI in n8n

This n8n workflow lets you run a chat-based due-diligence check for Polish contractors by automatically querying the Ministry of Finance VAT whitelist (VAT status + official details + bank accounts) and, when available, the KRS register—then returns a clear risk verdict and a readable summary.

What this workflow does

Built for practical Polish contractor due diligence, the workflow works like this:

• Chat request → identifier extraction: You ask a question in the n8n chat (typically including a Polish NIP, and optionally a bank account number). The workflow uses an Anthropic chat model with conversation memory to extract the NIP and any bank account data needed.
• VAT whitelist lookup (Ministry of Finance): It queries wl-api.mf.gov.pl to retrieve the contractor’s VAT status, registered details, and official bank accounts for today’s date.
• Optional KRS enrichment: If the VAT response contains a KRS number, it queries the Polish National Court Register (KRS) API (api-krs.ms.gov.pl) to fetch legal form and management/shareholder information.
• Bank account matching: If you provided an account number, it compares it against accountNumbers from the VAT whitelist response to determine whether it matches.
• Structured risk verdict + chat output: The workflow produces an overall verdict (OK, CHECK_FIRST, or DO_NOT_PAY) with key findings, then formats it into readable chat output while preserving the raw report data.

Use cases

• Procurement teams screening Polish suppliers before contract onboarding.
• Accounts payable workflows validating vendor VAT status and official bank details.
• SaaS operators building compliance checks for merchants/contractors across Poland.
• Automation engineers adding a reusable “VAT & KRS check” chat capability to their n8n projects.

Technical details

• n8nn8n-nodes-langchainchat trigger (chat-based interaction)
• n8nn8n-nodes-langchainlm chat anthropic (Anthropic model with conversation memory)
• n8nn8n-nodes-langchainagent and code nodes for processing/report structure
• HTTP Request nodes to wl-api.mf.gov.pl and api-krs.ms.gov.pl
• Outbound HTTP access required from n8n to both Polish APIs; configure Anthropic credentials (or swap the model node to another supported provider).