How do you activate international roaming on your cell phone?
On most cell phones, you activate it from Settings > Mobile Data > Data Roaming, or your carrier activates it automatically as soon as it detects you've arrived in another country. Some carriers leave it off by default to avoid surprise charges, so it's a good idea to check it before getting on the plane, not after landing.
The process varies a bit depending on the operating system, but the principle is the same in all cases: your cell phone needs your home carrier to have an agreement with at least one local network at your destination to be able to "lend" you its coverage. Without such an agreement, no matter how much you activate the option in the menu, the signal icon simply won't appear.
It's worth clarifying something that confuses many people: activating roaming is not the same as activating data roaming. You can leave voice and SMS roaming on (to receive calls and verification messages) and only turn off data roaming, which is what eats up your balance or plan the fastest.
What exactly is roaming and why is it sometimes so expensive?
Roaming is, in essence, an infrastructure loan. When you travel, your cell phone stops using your home carrier's network (because it no longer has physical coverage there) and starts connecting to a local carrier's network in the country you are in. That local carrier charges yours for letting you use its antennas, and your carrier passes that cost on to you, usually with a markup.
That's why traditional roaming can be expensive: it's not a fixed rate that your carrier freely decides; it's a chain of commercial agreements between companies from different countries, each with its own prices. And since these agreements change from one country to another (and from one carrier to another), it's almost impossible to give a single figure that applies to all cases.
If you want to understand how this looks "live" while you're connected and using data abroad, you can check our guide on real-time international roaming, which explains exactly what happens in the background when your phone switches networks after crossing a border.
Which countries does international roaming cover?
It depends entirely on your carrier and the plan you have. There is no "universal" roaming coverage: each carrier negotiates its own agreements, country by country, and those agreements can change without you knowing until you arrive and find you have no signal.
There are some factors that determine whether your roaming will work or not in a specific destination:
| Factor | What it means for you as a traveler |
|---|---|
| Carrier agreements | Your carrier must have a signed agreement with at least one local network in the country you are traveling to. No agreement, no signal, no matter what your phone settings say. |
| Type of plan contracted | Basic or prepaid plans usually exclude roaming, or limit it to a handful of neighboring countries. |
| Travel region | Blocks of countries with broad regional agreements usually have better roaming coverage than more isolated destinations or those with less outbound tourism from your country. |
| Trip duration | Some carriers limit the number of active roaming days within the same billing cycle, even if the country is covered. |
Therefore, the only reliable way to know if a specific country is covered is to check your own carrier's list of agreements before traveling, and not assume that "if it worked in one country, it will work in all of them."
A real-world example: a trip from Bogotá to Mexico City
Imagine you live in Bogotá and buy a ticket to spend five days in Mexico City. Before leaving, you check your phone settings and see the data roaming option is off. You activate it, get on the plane, and upon landing, your phone automatically searches for a signal.
If your Colombian carrier has an agreement with a Mexican network, within a couple of minutes you'll see the data icon appear and you'll be able to receive your WhatsApp messages and use the map to get to your hotel. So far, so good. The problem usually appears on the fifth day, when you check your carrier's app and discover that roaming was charged per megabyte consumed, not as a fixed package, and that watching videos, sending long audio messages, or using GPS all day ended up costing much more than you expected.
That's exactly the scenario that an alternative like a travel eSIM solves: instead of paying per megabyte consumed under a roaming agreement, you purchase a data plan in advance with a defined amount of GB for your five days in Mexico, install it before leaving Bogotá, and know from day one how much the entire trip's connection will cost you, with no surprise bills upon your return.
The question that really matters before traveling is not "do I have roaming?", but "do I know exactly how much it will cost me to use it?". If you can't answer that with a number, it's probably worth looking for a fixed-price alternative before leaving home.
How much do calls and data cost with your carrier abroad?
This depends entirely on the carrier and each person's plan, and these rates change quite frequently. Local carriers in different countries in the region—including mobile services linked to well-known retail chains, such as Móvil Éxito in Colombia—manage their own international roaming rates, which are not the same between them nor do they remain fixed over time.
Therefore, the honest answer is not a figure, but a method: before traveling, go to your carrier's app or website and look for the specific section "roaming rates" or "travel abroad." There you will find the current price per minute of call, per SMS, and per megabyte of data for the exact country you are going to, because even within the same carrier, these rates change from one destination to another.
What you can control without depending on any variable rate is to opt for a fixed-price data plan purchased in advance, such as a travel eSIM: you pay once for a defined amount of GB and you already know the total cost before getting on the plane, without depending on how much your carrier charges per megabyte that month in that particular country.
Which network does your cell phone use when you are outside your country?
When you activate roaming, your cell phone does not use your home carrier's network: it connects to the network of a local carrier in the country you are in, according to the agreement that exists between both companies. This applies whether your carrier has its own infrastructure or if it is a mobile virtual network operator (MVNO), that is, a company that offers mobile service without owning its own antennas and that leases capacity from a host network through a commercial agreement.
MVNOs are common in several countries in the region: there are mobile phone brands linked to banks, retail chains, or supermarkets that operate under this model. The fact that a carrier is an MVNO does not mean that its service is worse; it simply means that, for international roaming in particular, it depends on two layers of agreements instead of one: the agreement with its host network in the country of origin, and the roaming agreement of that host network (or the MVNO itself) with carriers abroad.
If you want to better understand how this compares to another form of connectivity, later in this guide you can review the difference between traditional roaming and eSIM, which explains in more detail what actually changes for you as a user.
International roaming vs. travel eSIM: which is right for you?
Roaming allows you to continue using the same number, which is convenient if you need to receive work calls or bank SMS while traveling. Its main disadvantage is that the cost of data is usually variable and unpredictable, unless your carrier explicitly offers a closed roaming package for that destination.
An eSIM is a digital SIM card that is installed by scanning a QR code, without needing to open the phone's tray or change your physical SIM. Many recent cell phones allow you to keep your physical SIM active (with your local number, for calls and verification SMS) and a data eSIM for the trip at the same time: you don't have to choose between one or the other, and that's a feature that few people take advantage of because they don't know it exists.
Before deciding, it's useful to review the detailed comparison between eSIM and traditional roaming, and also confirm that your cell phone is compatible by checking the list of eSIM-compatible cell phones, because not all models, even some relatively recent ones, have this feature enabled.
Comparison: local carrier roaming vs. international eSIM
| Aspect | Roaming with your local carrier | Data eSIM for travel |
|---|---|---|
| Activation | Automatic upon arrival, or manual from phone settings | Installed before or during the trip by scanning a QR code |
| Cost | Your carrier's rate, may vary by day, MB, or country | Data plan with defined GB and price before traveling |
| Your local number | Remains active for calls and SMS | Remains on your physical SIM; eSIM is used for data only |
| Coverage | Depends on your carrier's agreements country by country | Depends on the eSIM provider's catalog (e.g., PuraSIM covers more than 200 destinations) |
| Support if something goes wrong | Your home carrier's, according to their usual hours | In PuraSIM's case, 24/7 support in all languages via email and WhatsApp |
Neither option is "the right one" in all cases: if you're making a single short call and need to keep your number visible, your carrier's voice roaming might suffice. If what you'll be using most is the internet (maps, social media, messaging), a fixed data plan is usually simpler to calculate than per-MB roaming.
How to choose a data plan for your next trip
No need to overcomplicate it: just check a few points before buying any plan, whether from your carrier or an eSIM provider.
- Confirm your phone's compatibility. If you're opting for an eSIM, first check if your model supports it; not all phones have this feature enabled, even within the same brand.
- Calculate how many days you'll actually be connected. A weekend in a single destination is not the same as a multi-country tour.
- Think about what you'll use more: data or calls. If your priority is browsing and messaging, a fixed data plan is usually simpler to calculate than per-MB roaming.
- Check when you need to activate it. With an eSIM, you can buy weeks in advance and activate it just on the day you arrive; in PuraSIM's case, you have 180 days from purchase to activate it, so there's no rush to install it as soon as you buy it.
- Verify the installation process before traveling, not at the airport with your luggage in hand. The eSIM installation guide explains the complete step-by-step, and it usually takes just a couple of minutes to do it calmly from home.
Common mistakes that ruin your connection on a trip
Most connection problems on a trip are not due to bad luck, but to details that are overlooked before leaving. Some of the most frequent:
- Not checking network settings before traveling. Arriving in a new country and only then discovering that data roaming was off (or that it was never contracted) is one of the most common and easily avoidable setbacks.
- Confusing voice roaming with data roaming. You can have one active and the other not, which causes confusion when "calls are coming through but no map is loading."
- Leaving eSIM installation until the last minute. You need a Wi-Fi connection to install it, so doing it right after landing, without airport Wi-Fi, complicates something that takes a minute if done in advance.
- Not verifying the network name upon arrival. Sometimes the phone automatically connects to a different network than expected, with worse coverage, when another option was available in the same place.
If you want to review a more complete list of typical failures and how to solve them step by step, the common eSIM problems guide covers the most frequent cases reported by travelers.
Frequently asked questions
Does international roaming work the same in all countries?
No. It depends on the specific agreements your carrier has with local networks in each country, so it can work perfectly in one destination and have no coverage in the neighboring country.
Do I need to disable roaming to avoid overspending?
Only if you don't have any roaming package contracted and want to avoid charges per megabyte consumed. If you have already purchased a fixed-price data plan, such as an eSIM, you don't need to turn off anything additional once installed.
Can I use WhatsApp with roaming without extra charges?
WhatsApp uses mobile data like any other app, so it is charged the same as other data consumption, unless your carrier has a specific promotion that excludes it, something you should confirm directly with them.
What happens if I run out of data during the trip?
With traditional roaming, some carriers cut off service and others continue to charge you for additional consumption. With a data eSIM, you can usually buy an additional or top-up plan from the same app when you run out of contracted GB.
Does roaming affect battery life?
Yes, a bit: when the phone constantly searches for an available network in a new country, it consumes slightly more battery than when it is stably connected to a known network, although the effect is usually less once the connection stabilizes.
Is roaming useful for a short business trip?
It can be useful if you need to keep your number visible for calls, but it's advisable to check your carrier's exact rate for those specific days before assuming that "it's just a weekend, it shouldn't cost that much."
Can I have roaming and a data eSIM at the same time?
On most recent cell phones, yes: you can keep your physical SIM with voice roaming active for calls and use an eSIM only for data, without one function interfering with the other.
What do I do if my phone doesn't recognize any network upon arrival?
First confirm that airplane mode is off and that data roaming is activated in settings. If the problem persists, check if your carrier has a current agreement with a network in that specific country before assuming the phone is faulty.
Final recommendation
International roaming is not bad by definition: it's simply a chain of commercial agreements between operators, and like any chain, its cost and coverage depend on each link. For a short trip with little data usage, it may be sufficient. For a trip where you will depend on your phone for maps, messaging, and work, having a known fixed cost beforehand usually saves you both money and headaches upon your return.
If you prefer to know exactly how much you will pay for your next trip's connection before boarding the plane, you can check out the international eSIM collection, where each plan immediately shows the GB and price, with activation in approximately 1 minute once you arrive at your destination. And if it's your first time using an eSIM, the definitive guide to eSIM for travel is a good starting point before purchasing any plan.
