That depends on whereabouts you’re roaming with your iD SIM, @Tony Palmer. 

Hey there @Tony Palmer, welcome to Community!

Hey there, you can roam in the below countries like you can at home, and use data, calls and texts as you would in the UK, please see below:

https://www.idmobile.co.uk/help-and-advice/eu-roaming

If you joined/upgraded on/past 20st June 2023, you will be subject to the 30GB data fair usage policy. If your data allowances is lower than 30GB, your limit will obviously be your normal allowances, please see below:

https://www.idmobile.co.uk/help-and-advice/eu-roaming/fair-usage-policy

For countries outside the above, you can find the costs associated below:

https://www.idmobile.co.uk/help-and-advice/international-and-roaming-charges

You will need to enable roaming via the iD Mobile app/website and also via your phones own settings to use the phone. Please read the below for instructions on how to get set up:

https://community.idmobile.co.uk/community-archive-140/how-to-prepare-your-phone-for-a-trip-abroad-182

Thank you,

Tyler