Roaming and international calls, SMS and mobile data

When we use cellular services through our mobile phones in other countries or when we try to contact someone in other countries, then the roaming and international services become applicable. If you travel internationally or contact people abroad through your mobile phone, it is important to understand the concept of roaming and international calls, text messages and mobile data.

Roaming is when you are in a foreign country and use your mobile phone (cell phone) within that country for phone calls, texts or mobile data; international calling is when you are in your home country (the country your SIM belongs to), and you make a call to a number in a foreign country.

We all come across situations when we need to make phone calls to other countries or use our mobile phones in other countries when travelling abroad. Mobile operators provide a bunch of options to their customers for roaming as well as for international calls. Many operators also explain the differences between these two to make things clear. However, this topic can be a bit confusing, so this post aims to clarify it properly.

Difference between roaming and international

Both roaming and international calls deal with countries other than your home country. Roaming occurs when you use your mobile phone abroad, i.e. outside of your home country; international calls take place when you make a call from your home country to another country.

Home country, in this context, means a country from where you buy your mobile phone subscription, i.e. your SIM card. Of course, the mobile phone itself can be from anywhere.

For example, if you purchase your mobile phone subscription (SIM card) from Vodafone UK, your home country will be the UK for all communication through this subscription. However, if you use your UK mobile phone to call or text someone in another country, e.g. Germany, your mobile operator will charge you at international rates. Carrying on with the same example, if you travel to Germany, your UK phone may connect to Vodafone Germany if roaming is enabled on your subscription and phone. If you use any cellular services while roaming, your mobile operator will charge you higher rates than what they charge you in your home country. Mobile operators generally provide information about their international rates and roaming charges on their websites.

What is Roaming?

If you access any cellular services through your mobile phone when abroad, your mobile phone will start roaming. All voice calls, text messages, and mobile data will be subject to roaming charges when connected to a mobile network abroad. You can connect to a free WiFi to avoid data roaming charges.

When you travel abroad either on vacation or for business, it is good to be aware of the charges that will apply when using your mobile phone in the country you are going to. Mobile operators nowadays provide multiple options to roaming customers, but two kinds of roaming plans are usually available.

The one becoming more common is when your operator allows you to use your home allowance in the country you are travelling to at a specific day rate. So, for example, if you are a Vodafone pay-monthly (postpaid) customer in the UK, you can use your home allowance (i.e. UK minutes, texts and data) when you travel to USA/Canada for £6 per day. The roaming plans that allow using your home allowance abroad are very straightforward as they let you access all the services that are part of your home allowance in other countries also. So, for example, if your home country is the UK and you travel to Canada, a plan like the above example can let you use your home allowance for making calls to Canadian numbers and using mobile data. But you should always check your operator’s website (or contact them) to find out precisely what you can and can’t do with your allowance. For example, it may be that your operator has certain limits on the amount of data, minutes, and texts you can consume daily when abroad.

While the above model is more common for pay-monthly plans, there is another model where the operator can charge you per minute for making and receiving phone calls, per text for sending/receiving SMS, and per MB for using data abroad. This model is relevant mainly for ‘pay as you go’ or ‘pay as you use’ type plans that are usually available to consumers as well as businesses.

How can you switch roaming on/off?

The first and the most important thing to know about roaming is whether it is enabled on your mobile subscription or not. You can enable/disable roaming to control your costs. However, if you want to stay connected while abroad, you need the roaming service to be enabled on your tariff. Generally, the most expensive part of roaming is data roaming where you can be charged per megabyte (MB) of your data consumption while abroad. Mobile phones (smartphones) have options in the phone’s Settings menu to enable/disable data roaming.

If you have an iPhone (e.g. iPhone 13), you can go to Settings > Mobile Data > Mobile Data Options, which will take you to a screen with a slide button that allows you to enable/disable data roaming. If you have a US-based iPhone, the terminologies may look slightly different: Settings > Cellular > Cellular Data Options.

—How to enable/disable data roaming on iPhone—

If you have an Android Google Pixel phone (e.g. Pixel 5), you can go to Settings > Network and Internet > SIMs, which will take you to a screen where you can use a slide button to enable/disable data roaming.

—How to enable/disable data roaming on Google Pixel—

It is important to note that when you use the Settings menu on your smartphone to enable/disable roaming, it only enables/disables data roaming and not voice calls and SMS (text messages). Voice calls and text messages can still be facilitated on the phone if roaming is available on your tariff.

If you want to switch off roaming completely, you can contact your mobile operator to bar the service. If you just want to use WhatsApp and other data services on your phone while abroad, as a workaround, you can connect to any available WiFi network and get your SIM out.

What is international calling?

If you dial an international number from your home country to contact someone in another country, that will trigger an international call. The same concept applies if you send a text message (SMS) to an international number. International calls and texts are charged at international rates.

For example, if you live in the UK and make a voice call to a number in the US, that will be treated as an international call, and you will be charged accordingly. Depending on the country you are trying to call, international calls can incur additional charges for the mobile operators, which is why they charge you extra for international calls and texts. Typically, mobile operators charge per minute if you make an international call and per text if you send a text message (SMS) to an international number. In most countries, these charges apply only when you ‘make’ calls or ‘send’ text messages (SMS). You are generally not charged when you ‘receive’ an international call or text from someone. As always, it is important to check with your mobile operator because the rules can be different based on your country or mobile operator.

International calls and texts do not always have to be charged per minute or text, and other cheaper alternatives are also available. For example, some operators offer international bundles that can include a certain amount of international minutes and texts for certain countries. These bundles can be made available to the customers as bolt-ons or add-ons. But it is also possible for operators to have specialised tariffs inclusive of international minutes & texts. For example, some mobile operators in the UK offer specialised tariffs that include international minutes (and texts) that can be used to make calls to EU countries or USA/Canada.

One specific point to clarify here is that if you are in your home country (e.g. UK) and calling a friend who is a UK customer but currently roaming (e.g. in China), your call will still be a local call for you. It means that your operator will not charge you for an international call. However, your friend may have to pay roaming charges for receiving the call (depending on your friend’s roaming plan).

Lastly, when you make voice calls using online apps that use data (e.g. WhatsApp), you only pay for your data consumption, not the voice minutes. That makes it possible for you to call your friends on WhatsApp no matter which country they are in. When you are connected to a WiFi network abroad and make online voice calls through apps like WhatsApp, roaming is not an issue because it is an online call that does not use your mobile data. But international calls are important as there are situations when you need to dial international landline numbers, e.g. a hotel or taxi when you are abroad. Having some international minutes as part of your tariff can save the day in cases like that.

Here are some helpful downloads

Thank you for reading this post. I hope it helped you in developing a better understanding of cellular networks. Sometimes, we need extra support, especially when preparing for a new job, studying a new topic, or buying a new phone. Whatever you are trying to do, here are some downloads that can help you:

Students & fresh graduates: If you are just starting, the complexity of the cellular industry can be a bit overwhelming. But don’t worry, I have created this FREE ebook so you can familiarise yourself with the basics like 3G, 4G etc. As a next step, check out the latest edition of the same ebook with more details on 4G & 5G networks with diagrams. You can then read Mobile Networks Made Easy, which explains the network nodes, e.g., BTS, MSC, GGSN etc.

Professionals: If you are an experienced professional but new to mobile communications, it may seem hard to compete with someone who has a decade of experience in the cellular industry. But not everyone who works in this industry is always up to date on the bigger picture and the challenges considering how quickly the industry evolves. The bigger picture comes from experience, which is why I’ve carefully put together a few slides to get you started in no time. So if you work in sales, marketing, product, project or any other area of business where you need a high-level view, Introduction to Mobile Communications can give you a quick start. Also, here are some templates to help you prepare your own slides on the product overview and product roadmap.

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