XI VAT number checker: meaning, format and VIES check
Use this XI VAT number checker for Northern Ireland trade in goods. XI goes before the usual VAT registration number after HMRC confirms the business is recorded under the Windsor Framework. Check the XI number supplied by your customer or supplier in VIES below.
What does XI mean before a VAT number?
XI identifies VAT registrations used for Northern Ireland trade under the Windsor Framework. HMRC says a business must tell it that it is eligible and wait for confirmation before using XI in front of its usual VAT registration number.
An XI prefix describes the registration to check; it is not a successful VAT validation. Use the number provided by the business and keep the dated VIES response.
XI VAT number format and example
HMRC illustrates the format as XI 123456789 instead of GB 123456789: the XI prefix followed by the usual VAT registration number. This is a format example, not a verified business VAT number.
Do not replace GB with XI on your own. The business must first receive HMRC confirmation that it is recorded as operating under the Windsor Framework, then use XI on documentation with EU customers or suppliers.
How to use an XI VAT number checker in VIES
1. Read the VAT number on the invoice or other business document. Use the XI registration supplied by the business; do not change a GB prefix to XI just to make the number pass.
2. In the checker below, choose XI - Northern Ireland, enter the VAT number and press Check VAT number. You can also leave Country on Auto and paste the complete number beginning with XI.
3. Read the result and any business details returned. Copy or download the dated result for your records; an unavailable response means the check is unresolved.
XI, GB and IE: choose the right VAT check
XI is the Northern Ireland prefix supported by VIES. GB registrations are checked with HMRC, not VIES. IE is the prefix for Ireland; it is not interchangeable with XI.
Follow the prefix on the registration supplied by the business rather than choosing from its postal address. If the prefix is unclear, confirm it with the business before checking.
An unavailable XI check is not an invalid VAT number
Valid means VIES confirmed the number at the time of the check. Business name and address appear only when the responding register provides them.
Invalid means VIES did not confirm the submitted number. Check the prefix and digits with the business and ask it to confirm its registration status; do not treat a correctly formatted number as a successful validation.
Unavailable, timeout and capacity errors leave the check unresolved. Keep that response separate from invalid, check VIES status and retry later. There is no guaranteed recovery time.
XI VAT number checker questions
Can I check an XI VAT number in VIES? Yes. VIES supports XI for Northern Ireland, and the checker below accepts the XI prefix.
Can I turn a GB number into an XI number? Do not assume so. HMRC says the business receives confirmation that it is recorded as operating under the Windsor Framework before it starts using XI. Ask for the registration that applies.
Is XI the same as an Irish VAT number? No. Ireland uses IE; Northern Ireland uses XI for the relevant VAT checks.
Can I keep proof of the check? The checker lets you copy or download the dated result. Save the response you actually received; an outage is not evidence of an invalid number.
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