Originally Posted by
lsquare
Can you please explain why you kept your Optus and Taiwan Mobile numbers? Unless you need to make local calls, I would just roam with T-Mobile, which I get 5GB/month for international, or but a prepaid SIM if I'm there for a long time. Or I could always buy an eSIM.
Can you explain more about your 3 UK SIMs? Why? What's your use case?
Well some SIMs you can keep topping up, so you don't have to get another SIM card again and you can give out the foreign numbers for other people to call you.
Some SIMs will stay active without putting more credit on them for a few months. For instance, Vodafone Spain SIMs are like that. I had one for about a year that I recharged online every few months and used it for a couple of years whenever I went to Europe. All the traffic routed through Spain so the pings were kind of high but the speeds were good. Also included roaming in the US.
Not all these foreign SIMs let you recharge online using a US credit card though. So they are destined to expire unless they take US credit cards.