What is data roaming mean? How to reduce data charges while roaming abroad?


A mobile subscriber can browse the internet, and make and receive VoIP calls while roaming. This is possible because a mobile network operator supports data or the Internet.  A mobile operator defines data usage in bytes (KB, MB, GB, etc.).

The operator assigns a data bundle to a mobile subscriber (identified by IMSI) during internet recharge. Which has a volume and validity, such as 1GB of data with one-month validity.

Mobile internet usage resulted in a volume reduction of units relative to the initial volume. If you browse a page that is 10KB in size, the available data limit is reduced to 10KB.

Recharges may be for domestic or international data plans. For instance, if a T-Mobile USA subscriber is in New York, one MB of data costs.025 USD, whereas in the United Kingdom, each MB of data costs .2 USD. In general, international data roaming plans are significantly more expensive. Thus, it is critical to understand how to save data while roaming.

In this tutorial, we will explain how mobile data works over a GSM network, and what are the possible ways to reduce data roaming charges?

Why Data Roaming (International especially) is costly?

Data roaming means that a mobile user is not in the home network. The fundamental tenet is that the more resources you consume, the more you will pay.

The same is true for data roaming. A mobile subscriber connects to the mobile network in order to access the data. If the sim is local (T-Mobile subscriber in New York), network packets and data bytes attach and access data using only a few numbers of hopes.

All network elements (e.g GGSN, SGSN, HLR, etc.) and the connecting network cables belong to the local sim card provider. So no incur any additional cost to the third party if not in roaming.

How charges are calculated in roaming?  

When a T-Mobile USA user roams (for example, on the International UK network), there are multiple transit networks. The local network in the United States, a roaming network in the United Kingdom, and a transit network(s) that connects the local and roaming infrastructures.

Each network has its own pricing structure for each byte transferred between a mobile phone and the Internet. As a result, costs multiply by a factor of many.


How to reduce the cost of data roaming?

The cost savings come from three actions, reducing data usage, switching to alternative free data free sources, and purchasing roaming-friendly plans. This section will go into detail about each option.

Reduce Data Usage – The mobile phones come with an option to switch on/off data while roaming.  If you turn off that option and a mobile phone detects that the new network is not the home network it does not attach for data. The PLMN is the information that sim cards use to drive the network change.

  • Switch Off the data option for roaming.
    • Switch Off data usage on Roaming in Android ( Galaxy S8 reference example)-
      Open settings->Tap On Connections -> Mobile Networks.  Slid the button to the left to off data while roaming.
    • Switch Off data usage for Roaming in iPhone-
      Open settings-> Select Roaming Off in Cellular Data Options. For Details Check How to change settings for data.
  • MMS and Data usage – The normal text message uses only signaling, and mostly it’s (incoming) free. But MMS uses the internet,  so with data off, the MMS will also stop.
    Another way to stop MMS (Android) is, Go to Message App->Settings->More Settings->Multi Media Messages. Turn off the auto retrieve.
  • Set Data Usage Warnings if the device supports it.
  • Set data usage Cap, if have device has this option.

Alternative Options –  The alternative option is a WiFi network. These days you will find this option at all the places, Railway Station, Airport, Shopping Malls, Offices, etc. So  Just connect to WiFi and use the data in roaming.

SIM with Roaming Plans- Before moving abroad you can check data pack plans with the existing operator. If that does not suit you, there are options for traveling sim cards.  Generally, you can find shops at airports for travel SIM.

A travel SIM card provider is a kind of virtual network operator with the support of multi IMSIs in the card. When you land up in a country it will activate the IMSI local of that country.  So now you are local.