You can check an Irish VAT number through the EU's VIES service or, for domestic Irish checks, through Revenue. A VAT check is not the same as a CRO company search: it confirms a tax registration, while the CRO number identifies the legal company.
Quick answer: use VIES when validating an Irish VAT number for EU trade. Choose Ireland, enter the number without the IE prefix if the form adds it automatically, and retain the validation result with your transaction records.
How to check an Irish VAT number on VIES
- Open the European Commission's VIES VAT validation service.
- Select Ireland (IE) as the member state.
- Enter the VAT number exactly as supplied by the business.
- Submit the check and record the result, date and consultation reference where one is provided.
- Compare the supplied business identity with the legal company found through a CRO company search.
VIES is a search service that requests information from national VAT systems. A valid result confirms that the number is registered for relevant intra-EU transactions at the time of the check. It is not a credit check and does not prove that an invoice, bank account or representative is genuine.
What an invalid VIES result means
An invalid result does not automatically mean the supplier is fraudulent. The European Commission explains that a number may be invalid because it does not exist, has not been activated for intra-EU transactions, or its registration is not yet finalised. National services can also be temporarily unavailable.
If the result is invalid:
- check for missing letters, transposed digits and an incorrect country;
- ask the supplier to confirm the number in writing;
- retry later if VIES reports that a national service is unavailable;
- use the company's CRO number to verify its legal name and status; and
- seek tax advice before applying zero-rated or reverse-charge treatment where the evidence remains unclear.
VIES versus Revenue's domestic VAT check
VIES is designed for EU VAT validation. Revenue's current VAT registration guidance also describes a domestic VAT-number verification tool available through ROS and MyAccount. That tool returns a valid or invalid response for an Irish domestic number.
| Check | Use it for | What it establishes |
|---|---|---|
| VIES | EU cross-border VAT validation | Whether the quoted number is valid for the relevant EU VAT system |
| Revenue VAT verification | Irish domestic VAT checks | Whether the Irish VAT number is valid in Revenue's service |
| CRO search | Legal-company verification | Company name, CRO number, status, address and available filings |
CRO number, tax number and VAT number are different
These identifiers answer different questions:
- CRO number: assigned when the company is incorporated and used to identify its record on the Irish Companies Register.
- Tax Registration Number (TRN): issued by Revenue when a person or entity registers for tax.
- VAT number: used for VAT registration and invoicing. Its format can resemble another tax reference, but it should not be treated as proof of CRO registration.
If you only have a legal name, use our Irish company-registration-number guide to find the CRO record first.
Irish VAT number formats
Revenue's VIES guidance lists Irish VAT formats that include six digits and two letters, or seven digits followed by one or two letters. Older-style numbers can place a letter among the digits. Always validate the full number rather than deciding from its appearance alone.
A practical supplier-verification checklist
- Validate the VAT number using the appropriate official service.
- Keep the VIES result or reference with the invoice records.
- Match the legal name against the CRO company record.
- Confirm the company status is current and review its filing history.
- Check that payment instructions came through a trusted channel.
- For material credit exposure, perform broader Irish company due diligence.