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# How to verify an EU VAT number on VIES, look up a GLEIF LEI and check a company register in one workflow

Before issuing a zero-rated reverse-charge invoice or onboarding a European vendor, finance and compliance teams check whether the VAT number is active in VIES, whether the company holds an active Legal Entity Identifier (LEI), and what the national register lists for its legal form and address. Some developer libraries only test the check digits of a VAT string without asking the tax register at all. This guide walks through real VIES, GLEIF and Norwegian register checks with EU Business & VAT Checker and compares it against two rival VAT tools.

By OpenKrill. Published 2026-10-20. Every VAT check, LEI record and registry lookup below comes from live calls to [EU Business & VAT Checker](https://tools.openkrill.app/tools/eu-business) (`eubusiness.openkrill.app`), the European Commission VIES API, the GLEIF Global LEI Index and Norway's Brønnøysund Register Centre between 06:17 and 07:18 UTC on 2026-10-20.

## The short answer

Open the [EU VAT Checker and Company Registers](https://tools.openkrill.app/eu-business) page or connect `https://eubusiness.openkrill.app/mcp` to your assistant. Call `check_vat_number` to verify an EU or Northern Ireland VAT number against VIES, `find_company_lei` to query the GLEIF Global LEI Index, `lookup_company_registry` to search the French Sirene or Norwegian Enhetsregisteret register, or `company_from_domain` to resolve a company website to its registered legal entity.

## What our VIES VAT check returned for IE6388047V

We tested Irish VAT number `IE6388047V` across our server and three competing VAT tools on 2026-10-20. In 1,453 ms, `check_vat_number` queried the European Commission VIES service and returned:

- **Status:** `valid: true`, checked at `2026-10-20T06:17:06.520Z`
- **Registered legal name:** `GOOGLE IRELAND LIMITED`
- **Registered address:** `3RD FLOOR, GORDON HOUSE, BARROW STREET, DUBLIN 4`
- **Source and audit note:** Names the European Commission VIES source and notes that if you need a VIES consultation number as tax-audit proof, you pass your own VAT number with the check.

## How EU Business & VAT Checker compared with rivals

| Tool | Result on IE6388047V | Wall time | Score |
| --- | --- | --- | --- |
| **OpenKrill EU Business & VAT Checker** | `valid: true`, `GOOGLE IRELAND LIMITED`, Dublin 4 address, ISO check timestamp, VIES source attribution and consultation-number guidance | 1,453 ms | 10.0 / 10 |
| **VATComply API** (`api.vatcomply.com`) | Returned the same valid status, legal name and address, but omitted the data source and the check timestamp | 1,084 ms | 9.5 / 10 |
| **jsvat** (npm `2.5.4`) | Ran offline checksum math in 11 ms: returned `isValid: true` and `isValidFormat: true` without contacting VIES, so it cannot tell if a number was deregistered and returns no company name or address | 11 ms + local install | 6.6 / 10 |
| **Vatstack API** (`vatstack.com`) | Not run: requires an account and API key | not run | not run |

## Finding a company's LEI, national registry record and domain identity

A VAT check confirms tax registration, while GLEIF and national registers confirm legal form, registration numbers and headcount:

- **GLEIF Legal Entity Identifier lookup (`find_company_lei`).** Searching `name: "Siemens AG"` matched 28 records in the GLEIF Global LEI Index and ranked the closest legal-name matches first: `Siemens Aktiengesellschaft` (LEI `W38RGI023J3WT1HWRP32`, status `ACTIVE` and `ISSUED`, Munich, commercial register `HRB 6684` at `RA000304`, last updated `2026-09-01`, next renewal `2027-10-25`), followed by `Wohlfahrtsfonds der Siemens Schweiz AG` (`529900A2XKDE9KOXYE50`, Zurich) and `Siemens Healthineers International AG` (`8945006H4904GK255B88`, Steinhausen).
- **National company register search (`lookup_company_registry`).** Searching Norway's Enhetsregisteret with `country: "NO"` and `query: "Equinor"` matched 179 legal entities and returned `EQUINOR ASA` first: organisation number `923609016`, active status, legal form `ASA (Allmennaksjeselskap)`, registered `1995-03-12`, founded `1972-09-18`, address `Forusbeen 50, 4035 STAVANGER, Norge`, NACE activity `06.100 Utvinning av råolje`, and `21,231` employees.
- **Resolving a website domain (`company_from_domain`).** Passing `domain: "equinor.com"` cross-checked the company's own legal pages, Wikidata (`Q1776022`), GLEIF, Enhetsregisteret (`923609016`) and Verisign RDAP, returning confirmed confidence on every field and distinguishing the company's 1972 founding date (54 years old) from the domain registration date (`2011-06-15`).

## Connect it to your AI client

Add `https://eubusiness.openkrill.app/mcp` to your assistant, or follow the client install guides for [ChatGPT](https://tools.openkrill.app/integrations/eu-business/chatgpt), [Claude](https://tools.openkrill.app/integrations/eu-business/claude), [Cursor](https://tools.openkrill.app/integrations/eu-business/cursor) and [Pi](https://tools.openkrill.app/integrations/eu-business/pi). The 3 multi-step KYB recipes are downloadable as [eu-business-jobs/SKILL.md](https://tools.openkrill.app/skills/eu-business-jobs/SKILL.md).

Here is the JSON-RPC call from our VIES check:

```
{"method":"tools/call","params":{"name":"check_vat_number",
 "arguments":{"country":"IE","vatNumber":"6388047V"}}}
```

## What to watch out for in EU VAT and KYB checks

- **Relying on regex or checksum libraries for tax compliance.** A package like `jsvat` only checks whether a string fits a country's digit formula; only a live VIES query tells you whether the tax authority lists the number as active today.
- **Expecting every EU member state to return a company name on VIES.** Some member states, including Germany and Spain, do not release the trader's name or address through the public VIES lookup. Pair VIES with `find_company_lei` or a register check when you need the legal name and address.
- **Privacy rules on sole proprietors.** To protect personal data, our server leaves sole proprietors out of registry results and withholds VIES names that lack a corporate legal-form marker (such as `GmbH`, `SA`, `SRL` or `Limited`).

## Frequently asked questions

### How do I check if an EU VAT number is valid and which company it belongs to?

Call check_vat_number on eubusiness.openkrill.app/mcp with the two-letter country code (such as IE, FR or XI for Northern Ireland) and the VAT number without the country prefix. The tool queries the European Commission VIES database in real time and returns whether the number is active, the check timestamp, and the legal entity's name and address when the member state publishes them.

### Is there a free API to validate VAT numbers against VIES?

Yes. Both the European Commission's VIES REST endpoint and OpenKrill's EU Business & VAT Checker MCP server (https://eubusiness.openkrill.app/mcp) validate VAT numbers against VIES for free with no API key.

### How can I find a company's LEI or registry entry from its name or website?

Call find_company_lei with the company name to search the GLEIF Global LEI Index, lookup_company_registry to search the French Sirene or Norwegian Enhetsregisteret register, or company_from_domain with a website domain such as equinor.com to combine register, GLEIF, Wikidata and domain RDAP records in one call.

### How do I get a VIES consultation number for a tax audit?

Pass your own VAT country code and number alongside the customer's VAT number in check_vat_number so VIES issues an official consultation identifier for the check.

## Sources

- VAT, LEI, registry and domain runs: [EU Business & VAT Checker](https://tools.openkrill.app/tools/eu-business) (`https://eubusiness.openkrill.app/mcp`), read on 2026-10-20 between 06:17 and 07:18 UTC.
- European Commission VIES API: [ec.europa.eu/taxation_customs/vies/rest-api/ms/IE/vat/6388047V](https://ec.europa.eu/taxation_customs/vies/rest-api/ms/IE/vat/6388047V), read on 2026-10-20.
- Global Legal Entity Identifier Foundation (GLEIF): [GLEIF LEI Look-up API](https://www.gleif.org/en/lei-data/gleif-lei-look-up-api), read on 2026-10-20.
- Norwegian Brønnøysund Register Centre (Enhetsregisteret): [data.brreg.no/enhetsregisteret/api/enheter/923609016](https://data.brreg.no/enhetsregisteret/api/enheter/923609016), read on 2026-10-20.
- Competitors tested: [VATComply API](https://www.vatcomply.com/documentation) and [jsvat 2.5.4](https://github.com/se-panfilov/jsvat), tested on 2026-10-20.