What is international roaming and how does it work
International roaming is the service that allows your cell phone to connect to a phone network in another country using the same line you use at home, thanks to an agreement between your operator (for example, WOM) and a local company in the country you are traveling to. Coverage, speed, and cost depend on the destination and the contracted plan.
Technically, what happens is this: when your cell phone arrives in another country, it automatically searches for a network with which your operator has a roaming agreement. If it finds one, your line registers on that foreign network, and you can continue to receive calls, messages, and use data, even if you are physically far from WOM's infrastructure. The cost of that connection depends on what both operators have negotiated with each other, and on the commercial conditions that your operator passes on to you as a user.
This explains why roaming doesn't work the same in all countries: if your operator doesn't have an agreement with any network in the country you're going to, your cell phone may lose service, even if there is mobile coverage from other companies around you.
Which countries are included in WOM's roaming
There is no fixed and universal list, because international roaming coverage depends on the agreements in force between WOM and the local operators in each country, and those agreements change over time: destinations are added, conditions are renegotiated, or agreements that are no longer profitable for either party are terminated. Therefore, any list of countries you read in an article today may be outdated in a few months.
What you can do is check the current coverage directly in the WOM app or website before traveling, by looking for the roaming or international roaming section. There, it usually indicates, country by country, whether your plan includes the service automatically, if you need to activate an additional package, or if that specific destination does not have an agreement at that moment. Confirming it a few days before the trip—not the same day you leave—gives you room to resolve any surprises.
How to activate international roaming before traveling
The process varies depending on the operator, but generally follows a similar sequence. First, check if your current plan already includes international roaming or if you need to contract a specific package for the country you are going to; this can be confirmed in the operator's app or by speaking with support. Second, if activation is required, do so a few days in advance: some packages take time to apply or require SMS confirmation.
Third, check your phone's mobile data settings. On iPhone, it's usually in Settings > Cellular > Cellular Data Options > Data Roaming; on Android, in Settings > Network & internet > Mobile network > Roaming. Even if your operator confirms that the service is active, if this option is turned off on your phone, you won't have data when you arrive. Fourth, keep your operator's support number or chat handy in case you need to resolve something while abroad, when changing options is more limited.
A detail almost no one considers: the phone searches for a network as soon as it detects coverage, not when you decide to use it. That's why it's advisable to activate airplane mode before the plane lands, not after: this prevents the device from registering itself on a foreign network—and potentially starting to incur charges—while you are still getting off the plane or going through immigration.
How much does it cost to use international roaming
There isn't a single figure, because the cost of roaming depends on several variables that combine with each other. The important thing is not to memorize a price, but to understand what factors drive it to anticipate it before traveling.
| Factor | How it affects cost |
|---|---|
| Destination country | Each agreement between operators has different conditions; the same plan can cost differently in each country. |
| Plan type | Some plans charge per amount of data used, others per active connection day, and others include a closed package. |
| Package contracted or not | Activating a roaming package before traveling is usually cheaper than using data "on demand" without contracting it. |
| Use of calls and SMS | Voice and message roaming is usually charged separately from data, with its own cost per minute or per message. |
| Trip duration | Long trips may require renewing the data package several times, or switching to a plan with a larger volume. |
The most reliable way to know how much you will pay is to check the current conditions in your operator's app for the exact country you are traveling to, before you leave. Avoid relying on what roaming cost you one or two years ago: prices change.
In which countries is roaming usually cheaper or free
Some blocks of neighboring countries or those with regional economic agreements have more favorable roaming conditions between them, with reduced charges or even no additional cost for certain plans. Outside of these specific agreements, it is usual for international roaming to have some cost, either per contracted package or per usage.
Since these regional agreements change and do not apply equally to all operators or all plans, the only way to find out if your specific destination falls under any special condition is to consult directly with your operator before traveling, indicating the exact country you are going to.
The travel eSIM: the option many travelers don't know about
So far, we've talked about traditional roaming, which relies on your home operator having an agreement with a local network at your destination. But there's another way to get mobile data abroad that doesn't depend on such an agreement: installing a local or regional data profile directly on your phone, specifically for your trip, in addition to your usual line. This is called a travel eSIM.
An eSIM is a digital SIM card, integrated into the phone, that is installed by scanning a QR code instead of inserting a physical card. You can keep your usual line active for calls and messages, and at the same time have a data eSIM for internet in the country you are in, without touching the physical SIM you already use. If you want to understand how it works in more detail, there is a complete explanation of what an eSIM is and how it differs from a traditional SIM.
The main difference from operator roaming is that a travel eSIM is contracted separately, specifically for the destination or region of the trip, and its cost and conditions do not depend on any agreement your home operator may have. You can check before buying exactly how much data it includes and for how many days, without depending on whether WOM has an agreement with a local network in that particular country.
Operator roaming vs. travel eSIM: a comparison
Neither option is better in all cases; it depends on the destination, the duration of the trip, and how much control you want over spending. This table summarizes the most practical differences.
| Aspect | Operator Roaming (WOM) | Travel eSIM |
|---|---|---|
| Depends on | Agreement between WOM and a local operator in each country | A data profile you purchase separately, specific to the destination |
| Phone number | Your usual number is maintained for calls and SMS | Your number remains the same; the eSIM is used only for data |
| How it's activated | Activating roaming on the phone and, sometimes, a package in the operator's app | Installing a QR code before or upon arrival at the destination |
| Cost control | Can vary depending on pay-per-use prices if you haven't contracted a fixed package | You know in advance how much data and for how many days you've purchased |
| Coverage in several countries on the trip | Depends on the agreement in each country you visit | You can buy a regional eSIM or one for each country, depending on the itinerary |
Practical example: a trip from Bogotá to Mexico City
Imagine you live in Bogotá and are traveling to Mexico City for ten days for work. Before leaving, you check the WOM app to see if your plan includes roaming for Mexico or if you need to purchase an additional package; let's say there is an agreement, but the available data package is more limited than what you typically use on a normal workday with video calls and maps.
One alternative is to keep your WOM line active only for receiving calls and messages—like your bank's verification code or an urgent call—and, before your trip, install a data eSIM designed for Mexico, with the amount of gigabytes you estimate you'll need for those ten days. This way, you separate the two needs: your usual number still works so you can be reached, and the data you'll actually consume daily—maps, email, video calls, transportation apps—runs on a profile you purchased knowing exactly what it included.
This same scheme applies to any destination: the logic is not "roaming or eSIM," but rather using each for what it best solves in your specific case.
How to check if your phone is eSIM compatible
Not all phones support eSIM, although more and more models do: in general, mid-range and high-end phones launched in recent years tend to include this feature, while older or very basic models may not. In addition to the phone supporting it, it must also be unlocked (without operator lock) to be able to install a data profile different from your usual line.
The quickest way to confirm this is to check the specifications of your exact model, as within the same brand there may be versions with eSIM and versions without it, depending on the country where the device was sold. There is a list of eSIM-compatible phones that can save you that search. If you have doubts about errors when installing the profile, there is also a guide on common problems when using an eSIM and how to solve them.
Frequently asked questions
Does international roaming work the same in all countries?
No. It only works in countries where your operator has a current agreement with a local network, and the conditions—coverage, speed, cost—may vary from one country to another within the same plan.
Do I need to activate anything before traveling, or does roaming activate automatically?
It depends on the plan and the operator: some include automatic roaming within certain countries, while others require contracting a specific package before the trip. Additionally, you should always check that the data roaming option is activated in your phone's settings.
What if my operator doesn't have a roaming agreement in the country I'm traveling to?
Your cell phone may lose data or call service on that line, even if there is coverage from other companies in the area. In that case, an alternative is to install a specific data eSIM for that destination before traveling.
Can I use WhatsApp and maps without spending roaming data?
Yes, by connecting to Wi-Fi networks in hotels, airports, or cafes, which reduces mobile data usage. The limitation is that you depend on having Wi-Fi available at all times, which is not always practical if you are moving around the city.
What is an eSIM and how does it differ from a physical SIM?
It's a digital SIM card integrated into the cell phone that is activated by scanning a QR code, instead of inserting a plastic card. It can coexist with your usual physical SIM, so your usual number still works while you use the eSIM only for data.
How much in advance should I prepare before a trip?
Ideally, you should check your operator's roaming coverage or install your travel eSIM a few days before you leave, with a stable Wi-Fi connection, rather than leaving it for the airport or for when you're already at your destination.
Does the travel eSIM work on the same phone as my normal line?
Yes, provided your phone is eSIM compatible. Most current devices allow you to have your usual physical line and a data eSIM active at the same time, each serving a different function.
What if my phone is not eSIM compatible?
In that case, your option is still traditional roaming with your operator, carefully checking the conditions and costs before traveling, as you will not be able to install an additional data profile on a device that does not support this technology.
In summary
WOM's international roaming can solve your travel needs if your operator has a current agreement with a local network at your destination and the conditions of that plan suit what you need. The point is that this coverage and cost do not depend on you, but on an agreement between companies that changes over time—which is why it's always advisable to confirm it before each trip, country by country.
If you prefer to control how much data you buy and what it costs you, without relying on whether your operator has an agreement in that specific destination, a travel eSIM is an alternative that solves that specific part: you install it before you leave, you know in advance what it includes, and your usual line continues to work for calls and messages. It's available for more than 200 destinations, installs in approximately 1 minute, and you have 180 days from purchase to activate it when you need it—which gives you leeway even if you buy in advance and the trip's date changes. If you ever have questions during the process, 24/7 support is available in all languages via email and WhatsApp.
To start, you can check the definitive guide to traveling with an eSIM or directly view the collection of international eSIM destinations available. And if you still have doubts about which of the two options is best for your next trip, this comparison between eSIM and roaming delves into the criteria worth reviewing country by country, while this other note compares eSIM vs. physical SIM if your doubt is about the card format. And when you decide to install your eSIM, you can follow the step-by-step guide on how to install an eSIM.
