Roaming

Roaming is defined as the ability for a cellular customer to automatically make & receive voice calls, send & receive data, or access other services when travelling outside the geographical coverage area of the home network, by means of using a visited network. Roaming is technically supported by mobility management, authentication and billing procedures. Establishing roaming between network operators is based on - and the commercial terms are contained in - Roaming Agreements.

If the visited network is in the same country as the home network, this is known as National Roaming. If the visited network is outside the home country, this is known as International Roaming (the term Global Roaming has also been used). If the visited network operates on a different technical standard than the home network, this is known as Inter-standard roaming.

GSM Roaming, which involves roaming between GSM networks, offers the convenience of a single number, a single bill and a single phone with worldwide access to over 191 countries. The convenience of GSM Roaming has been a key driver behind the global success of the GSM Platform.

GSM Coverage Maps is a unique resource containing information supplied and approved by the members of the GSM Association.

Network, Services and Roaming information are continually updated to reflect the evolving situation worldwide. Interactive coverage maps, updated quarterly, allow you to navigate to see where exactly you can use your phone.

These definitions are provided simply to help industry discussion and do not indicate the scope of activities within the GSM Association.