@Magz
It depends on your tariff.
Guide: Roaming MegaGuide
https://www.o2.co.uk/international/using-your-phone-abroad
You can use WhatsApp over wifi to keep costs down.
To avoid daily travel charges you need to keep data off and just have wifi on.
You can also use a local sim, although no one at home will be able to contact you unless you telll everyone your number and calls and texts to UK will be expensive with a US sim
I have no affiliation whatsoever with O2 or any subsidiary companies. Comments posted are entirely of my own opinion. This is not Customer Service so we are unable to help with account specific issues.
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