GB vs XI EORI Numbers After Brexit, Explained

Since Brexit, moving goods between the EU and the UK means dealing with customs formalities that simply did not exist before. At the centre of those formalities sits the EORI number — and thanks to Northern Ireland's special status, there is now more than one type to understand. This guide explains the difference between GB EORI numbers, XI EORI numbers and EU EORI numbers, who issues them, and when you need each one.

Why Brexit created three EORI situations

An EORI number identifies businesses to customs authorities. Before Brexit, a single EU EORI covered trade across the whole bloc, and the UK was part of that system. After the UK left the EU customs union, the country was split into distinct customs territories for practical purposes:

• Great Britain (England, Scotland, Wales) — now treated as a third country by the EU.
• Northern Ireland — remains aligned with certain EU rules under the Windsor Framework (which updated the original Northern Ireland Protocol).
• The EU — the 27 member states, still operating one shared EORI system.

That split is exactly why a business trading in both directions may end up holding two — or even three — EORI numbers. If you are new to the concept, our guide to what an EORI number is covers the basics before you dive into the UK specifics.

The GB EORI number

A GB EORI number starts with the prefix GB and is issued by HMRC (His Majesty's Revenue and Customs). You need it to:

• Import goods into Great Britain from anywhere, including the EU.
• Export goods from Great Britain to the EU or the rest of the world.
• Make customs declarations or use customs simplifications in GB.

The format is straightforward: GB followed by your 12-digit number, which is usually based on your VAT number if you have one. Most GB EORI numbers look like GB123456789000.

Any business established in Great Britain that trades internationally needs a GB EORI. Non-UK businesses acting as importer or exporter of record in GB may also need one. For the full walkthrough, see our dedicated page on EORI numbers in the UK.

The XI EORI number

An XI EORI number carries the prefix XI and covers trade linked to Northern Ireland. It is also issued by HMRC, but it signals that the movement falls under the special Windsor Framework arrangements. You typically need an XI EORI if you:

• Move goods between Northern Ireland and the EU.
• Move goods between Northern Ireland and Great Britain (in certain declaration scenarios).
• Make declarations or get customs decisions in Northern Ireland.

An XI EORI is not automatic. To get one you generally need to already hold a GB EORI, and you must have a genuine reason connected to Northern Ireland — for example, a permanent business establishment there, or moving goods to or from NI.

Why XI matters for EU traders

Because Northern Ireland stays aligned with EU goods rules, an XI EORI is treated within EU customs systems in a way a GB number is not. This is what allows goods to move between NI and the EU without full third-country friction. For EU-based businesses that supply Northern Ireland, understanding the XI prefix is essential.

The EU EORI number

None of the above replaces an EU EORI number. If you are established in the EU, or you act as importer/exporter of record on the EU side, you still need an EORI issued by an EU member state's customs authority. That number begins with the two-letter country code of the issuing country — for example FR, DE, NL or IE.

An EU EORI is valid across all 27 member states. You only hold one, issued by the country where you are established or first make a customs declaration. You can confirm any EU EORI is active using our EORI number checker.

GB vs XI vs EU EORI at a glance

Dual-EORI setups for EU–UK traders

Many businesses that trade in both directions need more than one EORI. The most common combinations are:

1. GB EORI + EU EORI — an exporter that ships from Great Britain into the EU and handles customs on both sides.
2. GB EORI + XI EORI — a business that also moves goods to or from Northern Ireland.
3. All three — larger operators with GB, NI and EU activity, or e-commerce sellers using warehouses on multiple sides of the border.

The key point: an EORI identifies you to a specific customs authority. If you file declarations with HMRC and with an EU customs office, you generally need a number recognised by each.

A quick example

Imagine a German electronics distributor selling into Great Britain and supplying a customer in Belfast:

• For the German (EU) side, it uses its DE EORI.
• To act as importer of record into Great Britain, it registers for a GB EORI.
• To handle the Northern Ireland movements smoothly, it applies for an XI EORI.

Three numbers, one business — each doing a different job.

How to check and validate your numbers

Before you rely on any EORI, confirm it is valid and active. GB and XI numbers are validated through HMRC's UK service, while EU numbers are checked against the EU database. Our main EORI guide explains the registration steps for each region and links to the relevant official portals.

Your next step

Work out which side (or sides) of the border you actually make customs declarations on, then match each to the right EORI: GB for Great Britain, XI for Northern Ireland, and an EU EORI for the member-state side. If you trade both ways, plan for a dual setup early — applications take time and you cannot clear goods without the right number in place. Start with our full UK EORI guide to apply correctly the first time.