An economic operator registration and identification (EORI) number is needed for UK businesses. This helps with trade with the EU after the UK leaves the EU.
If there is a no-deal Brexit
If UK leaves EU without a deal, EORI number beginning with GB is a must. This helps with goods in/out of the UK.
There is no need for the number if goods only move between Northern and Ireland. You require it for imports and exports. This helps you move directly between Ireland and Great Britain. You don’t even have to go through Northern Ireland.
A business that as of now has a number beginning with GB can keep on utilizing it. It will be 12 digits in length and incorporate the VAT number where the business is as of now register for VAT.
Where a business is registered for VAT, HMRC sends out EORI numbers automatically. It’s advisable to keep the letter and a separate note of the number.
Businesses not registered for VAT
Businesses that are not registered for VAT will not receive an EORI number. They will apply for one if they wish to continue to trade with the EU post-Brexit.
This is a straightforward procedure and should be possible online on the Gov.uk site (see www.gov.uk/eori). Candidates typically get the number promptly. It might take up to five working days if HMRC needs to embrace more checks.
Forgotten or misplaced EORI numbers
A business that has lost its EORI number can contact the EORI helpline online using the contact form on the Gov.uk website at www.gov.uk/eori.
EU EORI number
A business that wishes to trade with an EU country also needs an EU EORI number. This starts with the country code that they wish to trade with. This can be obtained from the Customs authority of the EU country that the business will first trade with post Brexit.
Additional note: The following extract has been taken from the following website.