Good news if your plan on traveling in Europe over the summer as today as the day that EU roaming fees have ended.
This has been a long time coming as it has taken the mobile carriers a few years to finally scrap these fees, as of today, under European law, they are no longer allow to charge you extra for calls, texts and data when you travel in Europe.
Phone calls, SMS and going online with your mobile device from another EU country will be covered in the national bundle. The minutes of calls, SMS and megabytes of data that a person consumes abroad within the EU will be charged the same as at home.
As long as a person periodically travels and spends more time in his home country than abroad over any 4-month period, they will fully benefit from Roam Like at Home.
Now when you travel in Europe you will pay exactly the same as you do in the UK for calls, texts and data and this will also be part of your existing bundle.
If you have unlimited data then you need to check with your carrier about their fair use limit, if you go over this they will charge you €7.70 per gigabyte, this will be reduced to €2.50 in 2020.
If you travel outside of Europe you will still pay roaming fees, although soem companies like Three include some other countries in their plans, so it is worth checking with them to see which countries are supported.
Source Android Central