Guide
Tax ID Verification Online: Developer Guide 2026
Implement robust tax ID verification online. Our developer guide covers programmatic validation, error handling, caching, and Node.js/Python examples.
Jun 23, 202623 min
Blog
Developer guides and compliance resources for EU VAT validation.
Articles here cover the practical side of EU VAT validation: how to integrate VIES into checkout flows, what to do when VIES goes down, country-specific format quirks, and how EU compliance rules (reverse charge, OSS, DAC7) translate into API call logic.
Guides are written for developers who need to build correct tax handling, not for tax advisors. Each post includes working code examples and explains the compliance context just enough to understand why the code is structured the way it is.
Guide
Value Added Tax Germany: Developer's 2026 Guide
Explore value added tax germany for developers. Learn about 2026 VAT rates, reverse-charge, USt-IdNr validation, and B2B SaaS implementation.
Jun 22, 202623 min
Guide
How to Validate Company Registration Number: A Dev Guide
Learn how to validate company registration number with a resilient API. A step-by-step developer guide for EU/UK validation using Node.js & Python examples.
Jun 21, 202629 min
Guide
VAT Registration Number Switzerland: 2026 Ultimate Guide
Master your vat registration number switzerland with our 2026 guide. Learn correct format, verification, registration rules, and integration for Swiss UID
Jun 20, 202628 min
Guide
Validate VAT Number VIES: Official Tool & API Guide 2026
Validate your vat number vies using the official tool and SOAP API. Our guide covers common failures, caching, and why modern APIs are better in 2026.
Jun 19, 202621 min
Guide
VAT Validation UK for Developers: HMRC & Post-Brexit Rules
Guide to VAT validation UK for developers. Learn post-Brexit rules, query HMRC, and build a production-ready system with Node.js/Python examples.
Jun 18, 202624 min
Guide
How Much Is the VAT in UK 2026: Dev Guide
Discover how much is the vat in uk (standard rate 20%) in 2026. Get our developer guide to VAT registration, SaaS billing, reverse charges, and API validation.
Jun 17, 202625 min
Guide
Validate European VAT Number: Developer Guide 2026
Validate European VAT number with this guide. Handle VIES outages, caching, client/server logic using Node.js/Python & a modern API.
Jun 16, 202623 min
Guide
Tax Identification Number Switzerland
Learn about the tax identification number switzerland, including UID, AHV, and VAT formats. Get a clear guide to validate them for B2B billing in 2026.
Jun 15, 202622 min
Guide
EU VAT Identification Number: Guide & Automation 2026
Your complete guide to the EU VAT identification number. Master country formats, VIES validation, reverse charge rules, and automate checks in your app.
Jun 14, 202622 min
Guide
VAT Number Format a Developer's Reference Guide
A complete developer's guide to the VAT number format for every EU country, UK, CH, NO, & AU. Includes regex, examples, and a robust validation workflow.
Jun 13, 202628 min
Tutorial
Python Async VAT Validation with httpx and asyncio (FastAPI & Django Guide)
VIES latency (400ms–1.5s) blocks your async Python views if you use synchronous requests. Here's how to do it right with httpx, asyncio.gather, and FastAPI or Django async views.
Jun 12, 20269 min
Tutorial
VAT API Node.js: Quick Start Guide for Backend Developers
The shortest path from zero to a working VAT validation call in Node.js. No extra dependencies needed on Node 18+ — just fetch, your API key, and 20 lines of code.
Jun 12, 20267 min
Tutorial
VAT API Python: Integrating Tax ID Validation with Django & Flask
Concrete Django REST Framework views and Flask blueprint patterns for EU VAT validation. Uses httpx for async support and covers all four status codes with proper error handling.
Jun 12, 202610 min
Tutorial
React VAT Validation: Real-time Checks for B2B Forms
A complete React pattern for EU VAT validation: custom useVatValidation hook, debounced input, and a company confirmation UI that shows registered company name and address.
Jun 12, 202611 min
Guide
Tax ID Validation API: Global Coverage Beyond EU VIES
One API, 31 countries. TaxID validates VAT numbers across EU, UK, AU, NO, and CH — each routed to the right national registry — so you don't need separate integrations per country.
Jun 12, 20269 min
Guide
VIES API Integration: A RESTful Guide for Developers
VIES uses an archaic SOAP/XML interface that is painful to call directly. This guide explains how a REST wrapper works, what the responses mean, and how to build a production-ready integration.
Jun 12, 202610 min
Guide
Validate VAT Number API: How to Verify EU, UK, AU, CH, NO Tax IDs
One API call validates EU, UK, Australian, Swiss, and Norwegian tax IDs. This guide covers the country prefixes, format rules, expected responses, and error handling for each region.
Jun 12, 20268 min
Guide
Stripe EU VAT: Seamless Validation for Your SaaS Checkout
Stripe Tax calculates VAT but it does not validate whether a VAT number is real. This guide shows how to validate first, then set the tax_exempt flag so Stripe applies zero-rate correctly.
Jun 12, 202612 min
Compliance
Mastering EU VAT Compliance with a Real-time Validation API
EU law requires VAT number validation at the time of each transaction, not just at signup. This guide shows how to architect a real-time validation integration that satisfies both the legal requirements and your engineering team.
Jun 12, 202611 min
Guide
VAT & Tax ID Validation API for Developers
Everything a developer needs to start validating VAT and tax ID numbers via REST API: base URL, authentication, request format, response fields, status codes, and country coverage in one page.
Jun 12, 20269 min
Tutorial
VAT API PHP: Tax ID Validation for Laravel & Symfony
PHP integration patterns for EU VAT validation: a reusable Guzzle client, a Laravel service provider with facade, a Symfony dependency injection service, and PHPUnit test examples.
Jun 12, 202610 min
Guide
UK VAT Validation API: Post-Brexit Tax ID Checks for Developers
Since Brexit, UK VAT numbers are no longer part of VIES and must be validated via HMRC independently. This guide covers the GB format, what changed, and how to validate correctly in Node.js and Python.
Jun 12, 20268 min
Guide
Australian ABN Validation API: GST Number Verification Guide
Australian businesses use an ABN for all tax purposes including GST. This guide shows how to validate an ABN programmatically, what the response fields mean, and how to handle inactive registrations.
Jun 12, 20267 min
Tutorial
VAT API Go (Golang): High-Performance Tax ID Validation
Go's standard library net/http handles TaxID API calls without any third-party dependencies. This guide covers the typed client, context-based timeouts, all four status handling, and a sync.Map cache.
Jun 12, 20269 min
Tutorial
VAT API Java: Spring Boot Integration for Tax ID Validation
Spring Boot VAT validation using RestTemplate (sync) and WebClient (reactive). Includes a @Service class, Spring Cache integration, and JUnit 5 tests with MockServer.
Jun 12, 202610 min
Guide
Norway VAT Number (MVA) Validation API: Developer Guide
Norwegian VAT numbers end with 'MVA' and are registered with the Brønnøysund Register Centre — not VIES. This guide explains the format, validation endpoint, and how to handle all status codes.
Jun 12, 20266 min
Guide
Switzerland UID Validation API: Tax ID Checks for Swiss Businesses
Swiss tax IDs use the UID format (CHE + 9 digits). This guide explains the format, how UID differs from MWST registration, and how to validate both in Node.js and Python.
Jun 12, 20266 min
Guide
Developer Guides: Integrating VAT Validation API into Your Stack
All TaxID integration guides organised by language and framework. Find your stack and get from zero to a working EU VAT validation integration in minutes.
Jun 12, 20265 min
Guide
E-commerce VAT Validation: Automate Tax ID Checks at Checkout
For e-commerce platforms serving EU businesses, VAT validation at checkout is legally required to apply zero-rate B2B exemptions. This guide covers the checkout flow, error states, and platform-specific integration patterns.
Jun 12, 20269 min
Tutorial
VAT API Ruby on Rails: Tax ID Validation for E-commerce
Ruby on Rails VAT validation using Net::HTTP — no additional gems required. Includes a service object, controller concern, and RSpec tests with WebMock stubs.
Jun 12, 20268 min
Tutorial
VAT API .NET: ASP.NET Core Integration Guide
ASP.NET Core VAT validation using IHttpClientFactory and a typed HttpClient service. Includes dependency injection setup, controller usage, and xUnit tests with HttpMessageHandler mocking.
Jun 12, 20269 min
Guide
VAT API Error Handling: Timeouts, Fallbacks & Retry Strategies
The four things that can go wrong with a VAT API call and exactly what to do about each: format errors, invalid registrations, registry outages, and network failures.
Jun 12, 20269 min
Guide
How to Test Your VAT API Integration: Mocking & Staging Guide
Testing VAT validation means simulating all four status codes in a deterministic way. This guide shows how to mock the TaxID API in every major language and how to use test API keys to avoid consuming production quota.
Jun 12, 20268 min
Compliance
SaaS Billing VAT Compliance: Automate B2B Tax ID Verification
SaaS billing has unique VAT compliance requirements: subscriptions span months and VAT registrations change. This guide covers the full lifecycle — from first signup through monthly re-validation and audit trail management.
Jun 12, 202610 min
Compliance
Marketplace Seller VAT Verification: Onboarding Compliance Guide
Marketplaces that process payments on behalf of sellers must verify VAT registration under DAC7 rules. This guide covers the onboarding validation flow, batch re-validation, and the data you need to store.
Jun 12, 20268 min
Guide
India GSTIN Validation API: GST Number Verification for Developers
India's GSTIN is a 15-character alphanumeric tax ID that encodes the state, PAN, and registration type. This guide explains the format and how to validate it programmatically.
Jun 12, 20266 min
Guide
Canadian Business Number (BN) API: Tax ID Validation Guide
Canadian businesses have a 9-digit Business Number (BN) plus a 6-character program account suffix for GST/HST. This guide explains the format and how to validate Canadian tax IDs programmatically.
Jun 12, 20266 min
Compliance
B2B Invoice VAT Automation: Number Validation for ERP Systems
For ERP and accounts payable teams, VAT validation is both a buyer obligation and a seller verification step. This guide covers the validation architecture for invoice processing at scale.
Jun 12, 20269 min
Guide
Real-time Business Registration Number Lookup API Guide 2026
Perform a real-time business registration number lookup with our REST API. This developer guide covers EU VIES, Node.js/Python, and error handling.
Jun 12, 202624 min
Tutorial
WooCommerce EU VAT Validation: Beyond Format Checks with Real VIES Validation
WooCommerce validates VAT number format but never calls VIES. Here's how to add real-time VIES validation with PHP hooks, handle service_unavailable correctly, and build the audit trail in order meta.
Jun 11, 202610 min
Guide
VAT ID United Kingdom: Developer's 2026 Guide
A complete guide to the vat id united kingdom for developers. Learn formats, post-Brexit rules, verification methods, and robust validation for 2026.
Jun 11, 202622 min
Guide
Validate VAT Numbers in 31 Countries: A Deep Dive into the TaxID API
The TaxID API validates VAT and Tax ID numbers for 31 countries with a single REST endpoint. Here is what each country validates, what the registry returns, and the edge cases that trip up most integrations.
Jun 10, 202611 min
Guide
Bulk VAT Validation: Complete Developer Guide for ERP Imports and Re-validation Jobs
Validating a list of VAT numbers — CSV import, monthly re-validation job, ERP sync — requires a different approach from single-request checkout validation. Here's how to do it right.
Jun 10, 202611 min
Guide
United Kingdom Sales Tax: A Guide for SaaS & Developers
Your definitive guide to United Kingdom sales tax (VAT) for 2026. Learn about registration, rates, reverse charge, and how to automate compliance for SaaS.
Jun 10, 202624 min
Comparison
Choosing the Best VAT API: Comparison of Features and Pricing
Not all VAT APIs are equal. Some collapse service_unavailable into invalid. Some charge per-request even for format errors. Some have no SLA. This comparison covers what actually matters for production use.
Jun 9, 202610 min
Compliance
EU VAT Invoice Requirements for SaaS: The 16-Field Article 226 Checklist
Article 226 of the EU VAT Directive mandates 16 specific invoice fields. Missing any one of them makes the invoice non-compliant — even if you validated the VAT number correctly.
Jun 9, 20269 min
Guide
A Developer’s Guide to EU VAT Number Lookup
Learn how to build a resilient EU VAT number lookup system. This guide covers VIES, caching, error handling, and using a modern API for validation.
Jun 9, 202625 min
Tutorial
How to Validate EU VAT Numbers with VIES API (and Why Most Teams Use a Wrapper)
Calling VIES directly means SOAP, XML, ambiguous errors, and no caching. Here's how to do it both ways — raw VIES and a REST wrapper — with complete error handling.
Jun 8, 202612 min
Guide
VAT in Germany: A Developer's Guide to Billing & Checkout
A dev-focused guide to VAT in Germany. Learn about rates, reverse charge, VIES validation, and how to implement correct VAT handling in your SaaS checkout.
Jun 8, 202621 min
Compliance
EU VAT Rules for Digital Services: OSS, MOSS, and What Changed in 2021
EU VAT on digital services changed in 2021 with MOSS becoming OSS. Here's what that means for your SaaS: when OSS applies, when reverse charge applies, and how to route correctly in code.
Jun 7, 202611 min
Guide
Sales Tax in Norway: A Developer's Guide to MVA
A complete guide to sales tax in Norway (VAT) for developers. Learn about MVA rates, registration, invoicing, and how to handle Norwegian VAT in your SaaS.
Jun 7, 202626 min
Compliance
Automating B2B Invoice VAT Validation for Global Sales
Finance teams spend hours validating VAT numbers before issuing invoices. The same validation that takes a person three minutes per customer takes an API 200 milliseconds, with a logged audit trail included.
Jun 6, 20269 min
Guide
The Benefits of Real-time VAT Number Verification for SaaS Businesses
Manual VAT verification takes 10–15 minutes per customer and creates audit gaps. Real-time API verification eliminates the work, reduces fraud, and builds the audit trail automatically.
Jun 6, 20269 min
Guide
VAT ID Checker API: A Developer's Guide for 2026
Build a production-ready VAT ID checker with our developer guide. Learn to use a modern API (Node.js/Python), handle errors, and integrate with Stripe.
Jun 6, 202625 min
Guide
EU VAT Validation API: A Comprehensive Guide for B2B SaaS
The EU VAT validation problem is not just a compliance checkbox. It is an architectural decision that affects checkout latency, audit risk, and subscription billing. This guide covers all of it.
Jun 5, 202613 min
Compliance
Reverse Charge VAT for SaaS: A Developer's Implementation Guide
Reverse charge means the buyer accounts for VAT instead of you — but you must validate their VAT number, invoice correctly, and re-validate monthly. Here's how to implement each step.
Jun 5, 202610 min
Guide
VAT in Sweden: A 2026 Guide for SaaS & Devs
Comprehensive guide to VAT in Sweden for SaaS & developers. Learn 2026 rates, registration, reverse-charge, and validation. Stay compliant.
Jun 5, 202623 min
Tutorial
Stripe EU VAT: How to Validate Tax IDs Before Charging Customers
Stripe Tax calculates the right VAT amount and adds the reverse-charge annotation. It does not check whether the VAT number your customer entered is real. That gap is your liability, and this is how you close it.
Jun 4, 20269 min
Compliance
B2B vs B2C EU VAT for Digital Services: The Developer's Decision Guide
The B2B/B2C split is the most important decision in EU VAT compliance. Get it wrong and you either overcharge customers or expose yourself to VAT liability.
Jun 4, 20269 min
Guide
The Sales Tax API Guide for Developers (2026)
A complete guide to understanding and integrating a sales tax API. Learn about components, workflows, code examples (Node.js/Python), and best practices.
Jun 4, 202628 min
Tutorial
How to Integrate a VAT Number Check API into Your Checkout Flow
Adding a VAT field to checkout is three minutes of work. Doing it correctly — validating server-side, distinguishing VIES outages from invalid numbers, and applying zero-rate only when confirmed — takes this guide.
Jun 3, 202610 min
Guide
Reliable UK VAT Number Check: Your Guide for 2026
Perform a reliable UK VAT number check. Validate manually, via HMRC/VIES, or integrate API for developers. Get accurate results for 2026.
Jun 3, 202622 min
Guide
What is a VAT Validation API and Why Your SaaS Needs It
Three things happen without a VAT validation API: you zero-rate invoices for unregistered buyers, your finance team manually googles VAT numbers, and a tax audit turns into a liability exercise. Here is how an API fixes all three.
Jun 2, 202612 min
Guide
Ultimate Guide: Vat Identification Number Uk for 2026
Your complete guide to vat identification number uk for 2026. Learn its format, how to validate it via HMRC and APIs, and integrate it into your checkout flow.
Jun 2, 202622 min
Guide
Euro VAT Number: A Developer's Guide for 2026
A complete guide to the Euro VAT number for developers. Learn country formats, VIES validation, regex checks, and how to build a reliable system with an API.
Jun 1, 202621 min
Guide
UK VAT Number Format: A Developer's Guide for 2026
A complete guide to the UK VAT number format for developers. Covers GB/XI prefixes, regex, validation rules, checksums, and API integration for checkouts.
May 31, 202625 min
Guide
VAT Tax Switzerland: 2026 Guide for SaaS & Developers
Master vat tax switzerland for SaaS & developers. Get 2026 rates, registration thresholds, B2B rules, and automate VAT number validation for compliance.
May 30, 202622 min
Compliance
SaaS VAT Compliance: A Developer's Complete Guide for EU Markets
Selling a SaaS product to EU customers means navigating B2B vs B2C VAT rules, determining the place of supply, registering for OSS if needed, and generating compliant invoices. This guide covers the complete implementation.
May 29, 202614 min
Guide
VAT in Portugal: A Guide for SaaS & E-Commerce Teams
A complete guide to VAT in Portugal for B2B SaaS and e-commerce. Learn rates, registration, reverse charge, invoicing, and how to reliably validate VAT IDs.
May 29, 202624 min
Tutorial
How to Use a VAT Rates API: Developer Integration Guide
A VAT rates API lets you fetch current EU VAT rates programmatically instead of hardcoding rate tables. This guide covers integration patterns, caching strategies, and error handling for production billing systems.
May 28, 202610 min
Guide
EORI Number Lookup: A Developer's Guide to Validation
Learn how to perform an EORI number lookup manually and with an API. This guide includes code examples in Node.js and Python for automated EORI validation.
May 28, 202625 min
Tutorial
VAT for Developers: The Complete 2026 Implementation Guide
VAT is a consumption tax collected at each stage of the supply chain. For developers, this means implementing rate lookup, customer classification, VAT number validation, and compliant invoice generation. This guide covers all of it.
May 27, 202612 min
Guide
What Is the VAT Tax in Italy: 2026 Guide
Discover what is the vat tax in italy, how it works for B2B/B2C sales. Our 2026 guide covers rates, reverse-charge, and validating VAT IDs.
May 27, 202622 min
Country Guide
France TVA Rates 2026: Complete Guide for Businesses and Developers
France has four TVA rates: 20% standard, 10% intermediate, 5.5% reduced, and 2.1% super-reduced. Understanding which rate applies to your products is essential for correct billing of French customers.
May 26, 20268 min
Guide
European Union VAT Identification Number: A Dev's Guide
Learn what a European Union VAT identification number is, its formats, and how to validate it. A complete guide for developers on VIES, regex, and using an API.
May 26, 202623 min
Country Guide
Germany VAT Rates 2026: Standard, Reduced & Zero-Rated Explained
Germany applies a 19% standard VAT rate (Umsatzsteuer) and a 7% reduced rate. This guide explains which categories qualify for each rate, special rules for digital services, and how to integrate German VAT rates into your billing system.
May 25, 20268 min
Guide
VAT Tax Germany: A Developer's Guide for 2026
A developer's guide to VAT tax Germany. Learn how rates, reverse charge, validation, and invoicing rules impact your code, APIs, and checkout flows in 2026.
May 25, 202625 min
Guide
EU VAT Rates by Country 2026: The Complete Guide
VAT rates across the EU range from 17% (Luxembourg) to 27% (Hungary) for the standard rate alone. This guide covers all 27 EU countries, the different rate types, and how to look up rates programmatically via API.
May 24, 202610 min
Guide
VAT in Denmark: A Developer's Guide to 2026 Rules
A developer's guide to VAT in Denmark. Learn 2026 rates, registration, reverse-charge for SaaS, and how to validate Danish VAT numbers via API.
May 24, 202624 min
Guide
Dutch VAT Rate 2026: Your Complete Compliance Guide
Our 2026 guide clarifies the Dutch VAT rate, covering 21%, 9%, 0% rates, reverse-charge rules, and automating SaaS validation via Stripe & TaxID.
May 23, 202624 min
Guide
Master European VAT Identification Number Validation
Developer guide to the European VAT identification number: formats, VIES validation, common errors, and building resilient compliance checks.
May 22, 202625 min
Guide
VAT Percentage in France A Developer's Guide (2026)
Learn the current VAT percentage in France for 2026. This guide covers rates, B2B/B2C rules, VIES validation, and developer tips for SaaS billing.
May 21, 202623 min
Guide
EU VAT ID: A Developer's Guide to Validation (2026)
Learn what an EU VAT ID is, why it matters for B2B sales, and how to reliably validate numbers in your checkout flow. A complete guide for developers.
May 20, 202620 min
Guide
VAT VIES Check: A Developer's Guide to EU VAT Validation
Learn how to perform a VAT VIES check correctly. This guide covers the VIES API, error handling, caching, and code examples for a resilient implementation.
May 19, 202621 min
Guide
European VAT Numbers: A Developer's Guide for 2026
A dev's guide to European VAT numbers. Learn formats, validation via VIES or API, and how to build resilient B2B SaaS billing systems for the EU market.
May 18, 202626 min
Guide
How to Check Tax ID Numbers Reliably
Learn how to check tax ID numbers reliably. Our guide covers local formats, VIES/IRS lookups, and using an API for billing and checkout.
May 17, 202622 min
Guide
VAT Number Lookup: A Developer's Guide for 2026
Learn to build a resilient VAT number lookup for your SaaS or e-commerce app. This guide covers VIES pitfalls, API integration (Node/Python), caching, and UX.
May 16, 202624 min
Guide
How to Calculate VAT Tax: A Developer's Guide for 2026
Learn how to calculate VAT tax with formulas for exclusive/inclusive prices, reverse charge rules, and API examples. A practical guide for developers.
May 15, 202625 min
Tutorial
EU VAT Validation in Node.js: Complete Tutorial with Error Handling
Copy-paste Node.js / TypeScript implementation for EU VAT validation with proper error handling, caching, and test coverage.
May 14, 202614 min
Compliance
EU VAT Number Validation: The Complete Developer Guide (2026)
VIES is SOAP-based, unreliable, and has no caching. This guide explains how EU VAT validation works end-to-end, how to handle downtime gracefully, and includes copy-paste code examples in four languages.
May 11, 202615 min
Comparison
Free EU VAT Validation APIs: Honest Comparison of Limits and Trade-offs
'Free' means different things. Vatlayer's free tier is HTTP only. Vatstack caps at 20 requests. The real comparison before you commit.
May 8, 20269 min
Compliance
DAC7 Compliance for Marketplace Platforms: VAT Verification Requirements
EU platforms with 30+ sellers or €2,000+ threshold must collect and validate seller tax IDs under DAC7. Here is the technical implementation.
May 1, 202611 min
Country Guide
German VAT Number Validation: USt-IdNr Format, VIES, and Common Errors
German USt-IdNr numbers follow DE + 9 digits. But format-valid numbers can still fail VIES. Here is everything a developer needs to know.
Apr 24, 202610 min
Comparison
Vatstack vs TaxID: Which EU VAT API Is Right for You?
Vatstack's free tier caps at 20 requests/month. TaxID starts at 100 free. Here is the full breakdown.
Apr 17, 202610 min
Compliance
B2B VAT Exemption in EU SaaS: What Your Billing System Must Do
Reverse charge sounds simple but the implementation details trip up most SaaS billing engineers. Here is what your system must do to stay compliant.
Apr 10, 202612 min
Tutorial
VIES Downtime: How to Build a Resilient VAT Validation Flow
VIES has scheduled and unscheduled maintenance windows. An API that hard-fails when VIES is down will block legitimate customers with valid numbers. Here is how to build a resilient flow.
Apr 3, 202612 min
Country Guide
Netherlands VAT Number Validation: BTW-nummer Format, VIES, and Code Examples
Dutch BTW numbers have a unique format: NL + 9 digits + B + 2 digits. The literal 'B' is not a separator — it is a mandatory part of the number. Omitting it is the most common Dutch VAT format error.
Mar 27, 202610 min
Country Guide
Polish VAT Number Validation: NIP Format, VIES, and Code Examples
Polish NIP numbers use PL + 10 digits. The 10th digit is a check digit computed from the first 9. Polish numbers are often formatted with hyphens on invoices — strip them before validation.
Mar 20, 20269 min
Country Guide
Spanish VAT Number Validation: NIF Format, VIES, and Code Examples
Spain's NIF is one of the most complex EU VAT formats: ES + a letter or digit + 7 digits + a letter or digit. The first character encodes the company type. Here is everything a developer needs.
Mar 13, 202611 min
Country Guide
Italian VAT Number Validation: Partita IVA Format, VIES, and Code Examples
Italian Partita IVA numbers follow IT + 11 digits. The last digit is a computed check digit, and Italy's VIES endpoint is one of the less reliable in the EU — here is everything you need to build a resilient integration.
Mar 6, 202610 min
Country Guide
French VAT Number Validation: TVA Intracommunautaire Format, VIES, and Code Examples
French VAT numbers use FR + 2 alphanumeric characters + 9 digits. The first two characters can be letters or numbers — one of the few EU formats with an alpha component after the prefix.
Feb 27, 202610 min
Ready to build?
The guides above describe the problem. These pages show you how to implement it.
Node.js VAT validation guide
Express + Fastify integration with full error handling.
Python VAT validation guide
requests / httpx for Django and FastAPI.
Free VAT API — 100 calls/month
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Compare EU VAT APIs
Honest comparison with Vatstack, Vatlayer, Avalara, and others.