HMRC has now written to over 145,000 VAT-registered businesses across the UK with a Brexit update. The letters explain changes to customs, excise and VAT in the event that the UK leaves the EU without a deal, and what businesses can do to prepare. There are a number of different versions of the letters some of which are specific to the circumstances of businesses in Northern Ireland.If the UK leaves the EU without a deal then UK businesses will be responsible for making customs declarations. HMRC is encouraging businesses that trade with the EU to ensure they register for a UK Economic Operator Registration and Identification (EORI) number. This identification number will be required even if the business appoints a customs agent to assist in making customs declarations.HMRC is also introducing a new Transitional Simplified Procedures (TSP) for customs, to make importing easier for the initial period after the UK leaves the EU, should there be no deal. The TSP will allow businesses to transport goods from the EU into the UK without having to make a full customs declaration at the border and postpone paying any import duties.The procedures outlined above do not currently apply to importing or exporting goods between Northern Ireland and Ireland. The government continues to stress that it will do everything possible to avoid a hard border between Northern Ireland and Ireland whatever the circumstances of a ‘no deal’ Brexit.