eSIM has been working great for me when traveling to the UK and Canada from the USA. I have an iPhone 13, which allows up to two eSIMs or one physical SIM and

eSIM has been working great for me when traveling to the UK and Canada from the USA. I have an iPhone 13, which allows up to two eSIMs or one physical SIM and one eSIM to be active simultaneously. The first time I did this, my primary account was a T-Mobile Connect SIM that didn't allow out of USA roaming. By the second time, I'd transferred to a Boost Mobile eSIM, which, again, doesn't allow out of USA roaming. When traveling I just bought a data eSIM from a random provider ('BNE' and 'GlobaleSIM'). They have different pricing for varying combinations of data vs. time - a fixed amount per day, a fixed amount with a month time limit, a fixed amount with no time limit etc. They're very cheap compared to how things used to be (I think I paid about $15 for 3GB over two weeks in the UK, and $9 for 1GB of data with no time limit in Canada). One thing I did not expect is that my US number kept working! With WiFi calling switched on, the non-roaming T-Mobile and Boost accounts just kept working by using VoIP over the data SIM's internet connection.