USA SIM card for iPhone

Can anyone recommend a sim card that I can buy in the UK and take with me to the USA for use in Northern Michigan?

I don’t know about ones you can buy in the UK but I bought an AT&T one back in the US and add minutes to it whenever we travel back. Hopefully someone else knows of ones you can purchase here.

I ~think~ we had a Sky card at one point in Scotland, and had it in the phone when we traveled to the USA. We used the phone there, so....

You'll just want to be sure that whichever one you use, your phone is on the correct bands in the USA (which uses different ones than the UK). Not sure if it's a program with the latest smartphones or not, but since we only used "dumb" phones it was a make-or-break.