Why a Backup SIM is a Requirement for Foreign Travel
If you’ve traveled internationally enough, you’ve probably heard this before: “Don’t worry, your international plan will just work.” In theory, that’s true. In practice, it doesn’t always play out that way.
I’ve personally had multiple trips where my Verizon international plan was active, enabled, and paid for—and still didn’t work when I needed it most. No data. No reliable signal. Sometimes not even basic connectivity. When everything depends on that connection, the consequences can range from mildly annoying to genuinely stressful.
The photo above was taken during a river cruise on the Seine, with the Eiffel Tower in the background. It was an unforgettable vacation and an experience we’ll always treasure.
So why include that photo in a discussion about backup eSIMs? Because on this trip, our Verizon international coverage completely failed—on both my phone and my wife’s. Despite having an active international plan, we had no reliable connectivity when we needed it most.
If we hadn’t planned ahead with backup coverage, navigating the city, accessing reservations, and getting where we needed to go would have been far more difficult. In fact, we likely would have missed several key sites we’d wanted to see our entire lives. That experience reinforced just how critical a backup connection can be when traveling abroad.
That’s why I now consider a backup eSIM an essential part of foreign travel, right alongside a passport, power adapter, and travel insurance.
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eSim Providers To Consider:
When Your “Guaranteed” International Plan Fails
Major carriers like Verizon, AT&T, and T-Mobile generally do a good job with international roaming—but they are still dependent on local variables that can break at the worst moment. Things like:
- Local carrier partnerships (and which towers your phone is allowed to use)
- Network congestion (especially in busy airports and city centers)
- Regional coverage quirks (even within the same country)
- Device compatibility / band support
- Roaming provisioning working correctly at that moment
If any one of those fails, your phone can suddenly become far less useful than you expected. And if you’re landing after a long flight or trying to navigate a new city, that’s the last time you want to be troubleshooting.
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Why a Backup SIM (Especially an eSIM) Matters
A backup SIM isn’t about replacing your primary plan—it’s about redundancy. Think of it like carrying a spare credit card or packing a second charging cable. You hope you won’t need it, but if something goes wrong, you’re instantly glad you planned ahead.
A secondary SIM or eSIM gives you:
- An independent connection to local networks
- Immediate data access if roaming fails
- A way to troubleshoot issues without being completely offline
With modern eSIMs, it’s even easier: you can install it before you leave, keep it inactive until you need it, and avoid physically swapping SIM cards.
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Situations Where Connectivity Really Matters
There are plenty of times when being offline isn’t just inconvenient—it’s a genuine problem. Examples include:
- Navigating airports, ports, train stations, or unfamiliar cities
- Accessing maps, ride-share apps, and transit schedules
- Pulling up hotel confirmations, tour details, and reservation emails
- Using translation tools on the fly
- Handling flight delays, cancellations, or rebookings
- Reaching travel companions when plans change
In those moments, “I’ll just find Wi-Fi” isn’t always a reliable plan.
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Why This Matters Even More for Cruises
Cruise travel adds an extra layer of complexity. On a cruise, you might be:
- Embarking or disembarking in multiple countries
- Moving quickly through ports with limited time
- Switching between ship Wi-Fi, cellular roaming, and local networks
A backup eSIM helps ensure that the moment you step off the ship, you have working data—no guessing, no waiting, and no scrambling for a café with free Wi-Fi while your port day clock is ticking.
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It’s Also Okay to Disconnect (And That’s Great)
It’s worth saying clearly: not everyone wants to be connected while traveling—and that’s perfectly valid. For many people, travel (and cruising especially) is about unplugging:
- No email
- No notifications
- No constant connectivity
If that’s your goal, you might not want to use a backup SIM much (or at all). But even for travelers who prefer to disconnect, a backup eSIM can still be a smart safety net—something you activate only if plans go sideways or you need to handle an important issue.
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Redundancy = A Smoother Trip and Less Hassle
The idea is simple: when something is important, having a backup matters. There’s a saying you may have heard—“two is one, and one is none.” It’s a reminder that relying on a single option can leave you stuck when something goes wrong.
On trips where reliable data really matters, I take that mindset seriously and carry two backup eSIM options. In addition to the backup on my own phone, my wife’s phone is set up with a plan from a different eSIM provider.
That extra layer of redundancy means we’re not relying on a single carrier, a single app, or a single network relationship. If one provider has issues in a specific country or region, the other often works just fine. It may sound like overkill, but when navigation, reservations, or time-sensitive plans are involved, having multiple independent options can be the difference between a smooth day and a stressful one.
You’ll often hear influencers say something like, “Today’s video is sponsored by ___, it’s the eSIM I always use.” You’re not going to hear that from me. On the Europe trip mentioned earlier, we used Airalo, GigSky, and Saily across two phones. When our primary service failed, we didn’t miss a beat.
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Bottom Line
International roaming plans are convenient, but they’re not infallible. When they fail, it’s often at the worst possible time.
A backup SIM or eSIM isn’t about being glued to your phone—it’s about being prepared. For anyone who values flexibility, safety, and stress-free travel days, it’s a simple step that can prevent a lot of frustration.
These services are generally inexpensive, which makes it practical to pick up two or even three eSIMs from different providers. Since these plans are meant to act as a safety net for your primary carrier, you can start with the cheapest data option and add more only if you need it.
When connectivity matters, having a backup isn’t overkill—it’s smart travel planning.
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Top eSIM Providers for International Travel
If you’re adding a backup eSIM to your travel toolkit, it helps to know the leading providers that make it easy to stay connected overseas. Below are some of the most popular and reliable options for travelers in 2026:
Airalo
Airalo is one of the most widely used eSIM providers for global travel. It offers a large marketplace of data plans that work in many countries worldwide — with plans available for as few as a few days up to a year. Travelers appreciate Airalo for its affordability, easy app interface, and ability to purchase and install eSIMs before departure, making it ideal for short trips or light data users. I personally use Airalo and it has worked great! Hands on Review
GigSky
GigSky is another top choice, especially for travelers who want broad geographic coverage and flexible data options. It supports data plans in a very large number of countries and regions, with plans ranging from a few gigabytes for a week to larger packages for longer stays. Some of its plans can be installed once and used as you move between destinations — a strong option if you’re visiting multiple countries on a single trip. As an added bonus, GigSky works on cruise ships! I’ve also personally used GigSky and been very happy. Hands on Review
Holafly
Holafly stands out for offering unlimited data options in many destinations, which can be excellent for heavy data users or travelers who don’t want to worry about gigabyte limits. While generally a bit more expensive, unlimited plans can be great for long trips, streaming, or working remotely.
Ubigi
Ubigi offers both one-off eSIM data plans and subscription options that work in a large number of countries. Its plans can make sense if you want flexibility between pay-as-you-go and recurrent usage, and many travelers find it useful for both short trips and longer stays.
There are many other eSIM providers on the market (like Saily, Jetpac, and aloSIM) with varying price points and features, but the ones above are consistently among the most recommended for international travelers in 2025–2026. Choosing the right one depends on your travel style — whether you value budget pricing, unlimited data, or robust multi-country coverage.
Saily
Saily is a traveler-friendly eSIM provider known for simple setup, flexible data plans, and broad coverage in 200+ destinations. You can purchase and install a plan before you depart and manage everything from the Saily app — making it a good choice if you want straightforward connectivity without swapping physical SIM cards.
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How eSIMs Work
An eSIM (embedded SIM) is a digital version of a traditional SIM card that’s built directly into your phone. Instead of inserting a physical card, you download a carrier profile by scanning a QR code or using an app.
Once installed, the eSIM connects your device to local cellular networks just like a physical SIM would. Most modern smartphones can store multiple eSIM profiles at once, allowing you to switch between them in your phone’s settings.
For travelers, this means you can set up a data plan before you leave, activate it only if needed, and avoid hunting for SIM cards or relying entirely on roaming when you arrive.
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We had a wonderful time in Curaçao!
Pictured: 
Many cruise cabins have a common problem… lack of outlets. This has generally gotten better with newer ships, but can still be an issue. Even newer ships that have more cabin outlets, the outlets can be placed in such a way as to limit their usability. If two outlets are too close together… you can only use one.
