5 June 2026 · 7 min read
Caching VIES Responses Without Breaking Compliance
How long can you cache a VIES VAT check before it stops counting as compliant? TTLs, consultation numbers, Redis patterns, and audit-safe re-validation.
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Practical articles on EU VAT rates, VIES integration, compliance patterns, and regulatory updates — written for developers.
1 June 2026 · 9 min read
Reverse-Charge VAT for B2B SaaS: Node.js Implementation Checklist
A Node.js implementation checklist for the EU reverse-charge mechanism in B2B SaaS: buyer VAT validation, invoice flags, Article 196 citation, and audit evidence.
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29 May 2026 · 8 min read
Validate French VAT Numbers (TVA) in Node.js
Validate French TVA numbers in Node.js — regex with the 2-char key, VIES FR quirks, INSEE/SIRENE fallback, and how to design a resilient validation pipeline.
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25 May 2026 · 8 min read
VIES Consultation Number: What It Is and How to Store It
The VIES consultation number is the reference VIES returns when you validate an EU VAT ID. What it is, where to find it in the SOAP response, and how to store it as audit evidence.
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22 May 2026 · 7 min read
Validate German VAT Numbers (USt-IdNr.) in Node.js
Validate German USt-IdNr. in Node.js — regex format check, VIES DE quirks, BZSt fallback when VIES is down, and how to tell the two sources apart in your response.
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20 May 2026 · 6 min read
Validate EU VAT Numbers in Claude Desktop, Cursor, and ChatGPT — Official MCP Server
The official vatnode MCP server lets AI agents (Claude Desktop, Cursor, ChatGPT, Cline) validate EU VAT numbers against VIES, look up VAT rates, and check formats — directly in the chat. 30-second install, free tier, signed with npm provenance.
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2 April 2026 · 10 min read
EU VAT Rate Types Explained: Standard, Reduced, Super-Reduced, Parking, and Territorial Rates
A practical guide to all EU VAT rate types — standard, reduced, super-reduced, and parking — plus territorial exceptions for Spain (Canary Islands), Portugal (Azores, Madeira), France (DOM), and other EU regions where different rates apply.
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30 March 2026 · 6 min read
How to Handle VIES Downtime in Your Application
VIES national nodes go offline regularly. This guide covers retry patterns, queue-based approaches, BZSt fallback for Germany, and how to use the VIES_UNAVAILABLE error code correctly.
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30 March 2026 · 8 min read
EU VAT Rates 2026 — Complete Country-by-Country Guide for Developers
Full table of EU VAT rates 2026: standard, reduced, super-reduced, and parking rates for all 27 EU member states. Includes recent changes, currency, and how to access rates via API.
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