3G roaming is the process of using a 3G-enabled device in an area not covered by your service provider. In most cases this means using it abroad, though in some countries it can involve visiting a region which is not covered. When using 3G roaming, the data transfer will be routed via another service provider. The cost is paid through your standard bill but will usually be much higher.
A 3G device is one which uses the most commonly available and used system for high-speed data transfers. It is particularly popular with smartphones which have Internet access built-in. The system is also used for mobile broadband, in which a computer connects to the Internet via the cellphone network rather than a Wi-Fi or wired connection.
Roaming is used when a customer is in an area not covered by their own cellphone provider’s network. Without roaming, they would not be able to use cellphone services in this area. With roaming, their call is routed through another provider’s network. That provider then charges a fee to the customer’s own cellphone provider, which is then passed on to the customer.
While 3G roaming is most commonly associated with using a device in another country, it is possible to use roaming in areas of your own country which aren’t covered by your provider. This is more likely to be necessary than with voice calls which use the 2G network, which is usually much more widely available than 3G coverage. Roaming is not always possible as there is no requirement for networks to offer it, and it is dependent on them agreeing a partnership. The one exception to this is with emergency calls, which in many countries are automatically rerouted through a “rival” network if needed.
There has been some controversy over roaming costs paid by customers, with claims that providers charge considerably more than the actual fee they have to pay the network which handles the call or data transfer. When traveling to another country, it is particularly important to check the 3G roaming charges which will apply. For phone users in Europe, there are now restrictions in place which cap how much firms can charge for some type of roaming. However, 3G calls may not always come under these caps.
There is a particular hazard with using mobile broadband abroad. In such situations, your cellphone service provider may have a specified or “preferred” 3G roaming partner network in that country. However, your mobile equipment may be set to automatically connect to the strongest network available. If it then connects to a network which is not a preferred partner, the resulting charges may be considerably higher.