What is eSIM?

An eSIM is a SIM built into the phone's software, so a plan is activated by scanning a code rather than waiting for a plastic card in the post. All five brands here offer one: 019 Mobile, 1&1, 1pMobile, 2degrees and 3 Denmark each state eSIM support on their own sites. It suits anyone with a recent handset who takes more than one trip a year, or who wants to swap between plans without a shop visit. Check that your phone is unlocked before you move a number across.