All four of the UK’s core networks – EE, O2, Vodafone and Three – offer 5G . Other networks are known as Mobile Virtual Network Operators (MVNOs) and piggyback off the back of one of the core networks. So far MVNOs BT (EE), VOXI (Vodafone), Tesco Mobile (O2) and Sky Mobile (O2) have launched a 5G service.