Three Mobile customers can now use their inclusive minutes, texts and data for free in Ireland, Australia, Italy, Austria, Hong Kong, Sweden and Denmark.
Its new Feel At Home service, which launched last week, means anyone visiting any of these seven countries will be able to use their mobile in the same way as they would in the UK, without being charged extra (see our Cheap Mobile Roaming guide for cutting costs).
This means customers on a pay monthly contract with inclusive minutes, texts and data will be able to make calls, send texts and use the web while abroad, for free.
There are some limitations, however these won't affect most average users.
If your plan includes All-You-Can-Eat data, unlimited texts or more than 3,000 minutes, you will only be able to use up to 25GB of data, send 5,000 texts (back to the UK) and make 3,000 minutes of calls (back to the UK) in one month when using the Feel At Home service.
Three customers don't need to do anything to get the service. It will automatically activate as soon as you arrive in one of the listed countries, and will work on any local mobile network meaning you don't have to be on the Three network when abroad.
With other networks, you could pay up to £1.20/min when making and receiving calls, 40p for each text sent and £8/MB when using mobile internet in Australia, for example.
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Over the last few years, the EU has clamped down on roaming charges, and now customers cannot be charged more than 24p/min to make a call, 7p/min to receive a call, 8p to send a text and 46p/MB for using data when in the EU.
Three is currently the only UK mobile provider to allow customers to use inclusive minutes, texts and data abroad without paying extra.
The provider says it has no plans to expand the list of Feel At Home countries.
Three's marketing director, Thomas Malleschitz, says: "By abolishing expensive roaming charges in select countries, we are allowing our customers to get even more value from their minutes, texts and data abroad by removing the fear associated with staying in touch while travelling."