On 4 June, the European Commission advised economic operators to prepare for the consequences of the United Kingdom leaving the European Union on their imports and exports.   Following the UK’s withdrawal, UK inputs, including materials and certain processing operations, will no longer be considered EU origin for purposes of enjoying preferential treatment.   Whether a particular good qualifies depends on the rules of origin specified in each trade agreement between the EU and its trading partners.  The Commission advises EU exporters to treat any UK inputs as “non-originating” when determining the EU’s treatment of their goods post-Brexit and to take appropriate steps to be able to prove the preferential origin of goods without counting UK inputs as EU content.  Economic operators importing goods into the EU also are advised to take steps to ensure that the exporter can demonstrate compliance with EU preferential origin rules given the exclusion of UK inputs after Brexit.