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UK European Consumer Centre

What is Roaming?Person using a smartphone

What is International Roaming?

When you travel to a different country, your mobile phone keeps working - this means you are roaming.  You can make and receive mobile phone calls, write text messages, or download songs.  This means that your calls, texts, and other data services are being operated by a foreign network, as your home provided does not operate in that country.

For providing this service, the foreign network operator will pass on charges to your home operator.  Your home operator will then pass these extra costs on to you.  

See the flow charts below for the process taken in each of the scenarios 


Voice calls

a chart showing the process when a voice call is received 


Text message (SMS)

a chart showing the process by the operator when routing a message 


Multimedia message (MMS)

A chart showing the process taken by the operator when routing your mms 


Mobile data 

a chart showing the process when an operator allows data useag


The price of a mobile data service is very often based on the volume of the data, which is measured either in kilobytes (KB) or megabytes (MB).

  • An email is normally between 1 and 50KB
  • A page of your favourite online newspaper can be 100KB or more
  • To download a song you would have to transfer 2 to 5MBs of data.

Your operator will charge you a price that also includes the fee that the visited network charges the home operator to provide the service.