What is Roaming?

How Does Data Roaming Work?

It can be tricky if you want to use your smartphone and current SIM Card abroad. Is your phone unlocked? Can you change SIM Cards without any issues? What are the roaming service charges of your ISP? How fast is the internet going to be abroad?
Overlooking to turn off certain settings on your mobile phone when arriving in a foreign country can be a very costly experience. In short, if you are using the internet abroad with your own local SIM Card “Roaming” may impose certain charges. But what exactly is roaming?

The Definition of Roaming

Local Internet Service Providers usually do not have its own network infrastructure in foreign countries. They rely on partnerships with other ISP’s to provide you with an extended coverage area. What does that mean? You have signed a contract with network operator A in country A. Now, when you travel abroad to country B you will be using network operator B’s internet network. This is because network operator B has agreed on a partnership with your home network operator A.
Both mobile operators have agreed on a partnership in which they can provide mobile services to both customers at a negotiated price. This price plus the additional markup is your roaming fee while both operators have no extra costs at all.

How Do I Get Charged?

Every single time you browse the internet, make a call or send an SMS & MMS abroad you will get charged. Every essential function of a smartphone will cost you in roaming fees. If you are planning to use your smartphone in any of the previously mentioned kind you should remember possible roaming charges. 

Real Example

Roaming fees vary depending on your Internet Service Provider & the country in which you are roaming. It might result in a shocking bill at the end of the month if you do not look up the roaming rates before using it. This is an example of an American traveler who used roaming in the United Kingdom. The customer racked up almost US$5,000 (!!!) in mobile data charges without his knowledge.
Source : techzillo

Why Does Roaming Costs So Much?

Figuring out the exact retail prices for data roaming can be tricky. The lack of global regulations for roaming charges and a dedicated roaming network forces Internet Service Providers to negotiate their own terms and the rate at which they are offering to share their dedicated network with other partners.
Most consumers tend to think about data in GB (Gigabytes) and not in MB (Megabytes). Yet all roaming charges apply per MB used. This makes many people underestimate the real cost of roaming. Below is an example for standard roaming charges in the United Kingdom.




Within Europe | In-Bundle (per MB)Worldwide | In-Bundle (per MB)Within Europe | Out-of-Bundle (per MB)Worldwide | Out-of-Bundle (per MB)
T-MobileUS$0.26 – US$0.42US$1.92US$9.62
OrangeUS$0.3 – US$1.05US$0.3 – US$1.05US$3.85US$10.26
VodafoneUS$0.10 – US$0.26US$0.77US$1.28US$3.85
O2US$0.77 – US$1.03US$0.77 – US$1.03US$3.94US$7.70
ThreeUS$1.64US$3.85 – US$12.83


If you use 500MB on roaming on a two-week holiday in Europe with roaming enabled, you would end up paying US$640 in the best case scenario. In worst case scenario you would be US$6,415 lighter.

How To Avoid Roaming Charges?

We highly recommend to disable the roaming function on your smartphone so you can avoid horror stories like the one above.

Disable Roaming


Settings > Wireless & Networks > More- Mobile networks > ‘Data Roaming’ off.


Settings > Cellular Data > Cellular Data Options > Roaming Off.

Windows Phone

Settings- Mobile Network > Data Roaming Options > Don’t Roam

Be aware that menus can differ from phone to phone. Generally the paths look similar to the examples above though. If you want to be 100% sure that you do not rack up any additional costs, simply turn on the airplane mode.


Go Wi-Fi Only

You can try to put your cell phone on flight mode and connect it to a Wi-Fi network each time you have the opportunity. There are many places like cafés, shopping malls and parks where you can connect to a free Wi-Fi network.


Get a Local SIM Card

These type of cards offer cheaper rates than any international roaming charge. You can make voice calls, send text messages or browse the internet at the lowest prices. And here are the good news: if you receive any of these services there will be no roaming fee!


Restrict Phone Usage Time

Making and receiving calls or text messages can be very expensive when traveling as much as browsing on the Internet. Simply restrict your time on the internet so you can avoid roaming charges that will hurt your wallet. Also, you can make a list of the most important things you need to do, so you will not waste your time and your money staying connected to the internet.


Keep Track of Data Usage

There are smartphone applications that monitor your data usage and give you a warning signal when you are about to reach your established limit. With these apps, you will not exceed your limit so you will avoid extra data roaming charges.

How Much Data Is Being Used For Each Activity?

Keep in mind that that your usage may vary depending on what you do on the internet. The following estimates are based on typical file sizes.
ActivityData Size
1 email without attachments20KB
1 email with attachments
Browsing Web (1 Min)
Download 1 Song
Upload 1 Photo
Streaming SD Video (1 Min)11.7MB
Streaming HD Video (1 Min)41.7MB
Streaming 4K Video (1 Min)97.5MB
Online Games (1 Min)200KB

Whether you are off to discover the Golden Gate Bridge in San Francisco, want to explore the Eiffel Tower in Paris with a freshly baked croissant or want to tick Australia & New Zealand of your bucket list for travel destinations, SimOptions helps you realize all those dreams.

SimOptions provides Prepaid Travel SIM Cards for more than 200 worldwide destinations. Pick your next dream destinations, choose a SIM Card and discover new cultures without paying any roaming charges.