In 2012, several groups came together to establish UEF Spain. European federalists in Madrid, Galicia and Andalusia joined their forces with the existing associations Horitzó in Catalonia and JEF Europe. In November 2013, at the UEF European Congress the organisation was recognized as a full member. In September 2014, the network was joined by the UEF Castilla y Leon.
UEF Spain has managed to quickly establish a strong federalist network across Spain to work towards a federal Europe.