By Glenn Fleishman

July 28, 2025 8:15 AM PT

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Don’t overpay for cellular data while traveling

Travelers used to find themselves at a loss for cheap mobile data when traveling outside of their home country or region, and often wound up paying dearly for it. You now have an enormous range of options, but it’s always better to make plans before you leave.

I remember going to the United Kingdom in 2017, my first trip to Europe since 2000, and being armed with too little practical information. I knew that I should be able to drop into a Tesco or other store and find a cheap SIM plan that I could use for the several days I was there. I bypassed airport kiosks, warned that they were overpriced. Jet lagged, I probably wasted an hour figuring out what to do, but it worked just fine and it wasn’t a lot.

The next year, on a family trip with all four in our grouping, I had pre-purchased SIMs for each of our phones. On arrival, we sat at a café in the airport as I used a SIM remover tool and carefully took out each SIM (which I’d labeled with a Sharpie before leaving home), put it into a zip-seal bag, found the corresponding roaming SIM, and inserted that. Tedious, but better—and a lot more data for the dollar.

Now, we have the advantage of eSIMs: electronic SIMs that are a bit of circuitry that can reconfigure itself on demand to act like a physical SIM with none of the fuss. Most carriers worldwide have switched almost exclusively to them, allowing SIMs for just older legacy phones.

Starting with the iPhone XS/XR models, iPhones offered support for either a SIM or eSIM, with one active at a time. The iPhone 13 series introduced dual SIMs, allowing you to have either a SIM and an eSIM or two eSIMs active simultaneously. In the United States, Apple removed the physical SIM slot with the iPhone 14 introduction.¹

In 2022 and 2023, I travelled to multiple destinations in Europe with a combination of carrier-provided free international data and eSIM, and that was a breeze. But there were a lot of choices to make about cell plan, eSIM provider, and managing data between them.

Get familiar with eSIM installation and activation

One of the nicest things about eSIMs is that they’re not hard to deploy. Apple relies on an industry-supported standard and provides multiple paths to add an eSIM after purchase to an iPhone or to an iPad with a cellular modem. You can transfer an eSIM from a nearby phone when you’re migrating service, but for travel, you will either use a QR code or manually enter the eSIM number that is encoded in that QR code. Apple offers clearly written instructions.

In Apple’s eSIM overview, it notes that for a “new” iPhone, you need to be on an Wi-Fi network to activate services, except with a U.S. iPhone model starting with series 14. That applies to setting up base service.

When you’re adding a roaming eSIM, you need to make sure you have all the instructions required, like the QR code or other information, stored on your device or downloaded into an app, which many roaming providers offer. In some cases, you may only be able install the eSIM only when you’re in the area in which it offers service; in others, you can install in advance.

Installing may activate the SIM, starting a service days countdown, or your eSIM plan might have an expiration date for starting a service period. For instance, Airalo says to check your eSIM, as it may activate on installation; Holafly notes, “Install the eSIM before your trip and keep it turned off until needed to avoid unwanted data usage in multi-destination plans”; while Saily explains, “Your plan will automatically activate when you reach your destination or 30 days after you’ve bought it.” Read the instructions before purchasing!

After installing an eSIM, you can effectively archive or disable it when your service period or data usage limit is over. You can later reactivate it after you’ve topped up or renewed services through the eSIM provider, but you don’t need to scan a QR code or re-enter the eSIM information.

You can store up to eight eSIMs per device, though only one or two can be active at once, depending on your iPhone or iPad model. You can enable and disable eSIMs via Settings > Cellular or Settings > Cellular Data.

Check your carrier first

American carriers have a variety of options for service outside the United States. The cost split among them for data beyond the border is fairly stark, depending on how often you travel.

• Neighbors included (CA/MX): All carriers’ current plans include data in Canada and Mexico, save one Google Fi pay-as-you-go offering. These plans range from unlimited 128 Kbps service to full-speed service up to the monthly U.S. data limit of your plan before throttling.
• Day pass with monthly cap (AT&T, Verizon): AT&T and Verizon offer day passes that are capped at a monthly maximum (AT&T) or have a monthly option (Verizon). Both included daily data usage across 210+ countries² in the world. Big warning! If you use a single bit of data, one text, or one minute calling outside your included service on either carrier, they charge for you a day pass on their current “unlimited” plans that don’t include that country (more details below).
• Some level of unlimited included (Google Fi, T-Mobile): T-Mobile has a base level of 2G speeds (128 Kbps or 256 Kbps) in all their current plans and most of their legacy ones (I’m on legacy T-Mobile Magenta). The more you pay for basic service, the more data you get while roaming internationally each month and the higher the throttled rate. Google has one plan with a capped monthly usage and 256 Kbps thereafter outside the United States.
• Legacy pay-as-you-go charges (AT&T, Verizon): If you’re on a legacy plan, one without “unlimited” in the name, you might have to call, use a web site, or use an app to load an international day pass on AT&T or Verizon before you start using service in another country. Otherwise, they charge you $2,050 per gigabyte ($2.05/MB).

The “unlimited” in many cases means “up to X GB after which speeds are throttled or deprioritized in the United States, and, if unlimited is included for other countries, dropped to 3G or 2G rate.” However, a few top-tier “unlimited” plans don’t cap U.S. high-speed usage at all.

All service plans below have the price listed for a single line; multiple lines reduce the price dramatically, with 3 or 4 lines often dropping to half of the cost per line of a single line. Tax and fees are added to all monthly service charges noted, too.

AT&T

With AT&T’s current Unlimited plans, you get uncapped data, calls, and texts in and between Canada, Mexico, and the United States. There’s a footnote that says you could be dropped to 2G speeds without an explanation as to when or why.

AT&T’s International Day Pass is $12/day for unlimited data, talk, and texting when added to an unlimited plan, meaning the same limits you have for data for U.S. service.³ Additional lines that use international data on the same day are charged $6/day. It’s possible to add the pass to a legacy plan, but details of what you get then are buried deeply within a lengthy legal document. The cost is capped at 10 daily fees per line per month, so a maximum of $120 for a primary line and $60 for secondary ones.

AT&T top-tier Unlimited Premium PL plan ($85.99/mo.) includes unlimited data, voice minutes, and texting in 20 Latin American countries. There’s no plan with high-speed international usage beyond Canada, Mexico, and those 20 countries—you need a data pass.

If you don’t have a day pass added manually or automatically, the pay-as-you-go rates are $2.05/MB, which multiplies out to $2,050/GB.

Google Fi Wireless

Probably the simplest service to explain, Google Fi has two plan options that you can use with data outside the United States:

• Unlimited Premium ($65/mo.) includes 50 GB of usage per month in 200+ countries, then throttles to 256 Kbps for the remainder of the month.
• Flexible ($20/mo.) is $10/GB no matter where it’s used in those 200+ countries, including the United States.

Texting is free in those 200+ countries on both plans; calls are $0.20 per minute.

T-Mobile

Three of T-Mobile’s current plans and of some of its still-active legacy ones include unlimited international data at 128 Kbps or 256 Kbps in 215+ countries with some plans including higher-speed data. Calls are $0.25/minute except in Canada and Mexico, where they are free and unlimited; texting is unlimited worldwide.

With their current plans, you can opt for:

• Essentials Saver ($50/mo.): Canada and Mexico are included with 128 Kbps unlimited data usage. No other international usage can be had.
• Experience More ($85/mo.): You get 15 GB/mo. in Canada or Mexico and 5 GB/mo. in 215+ countries (or is it 213+?) before a 256 Kbps throttle.
• Experience Beyond ($100/mo.): This top tier offers 30 GB/month is Canada and Mexico and 15 GB/month everywhere else before a 256 Kbps throttle.

T-Mobile uniquely has an optional data pass you can add to plans, all three of which include unlimited calling during that period and use of the data as a mobile hotspot, something typically not allowed by carriers on any international roaming:

• 512 MB of data for $5 per day
• 5 GB of data for $35 across 10 days
• 15 GB of data for $50 across 30 days

Verizon

With either of the current two lower-tier Unlimited plans, a pass is automatically added when usage is detected; you can opt to add one for legacy plans that don’t start a pass for you. You can also subscribe to the Unlimited Ultimate plan for your line or lines ($90/mo.) to have international roaming included.

The Verizon TravelPass is $12/day in “210+ countries and destinations.” At that price, you get 5 GB a day at “high-speed” rates, which typically means the highest contracted Verizon has, likely 10 Mbps or much faster, depending on the carrier and region. After 5 GB, you’re dropped to “3G” speeds, which typically means a few Mbps. This daily pass also includes unlimited voice call minutes and text messages.

For $100/month, you get a full month with no additional charges and up to 5 GB per day and 20 GB per month before dropping to 3G speeds (1.5 Mbps). Weirdly, this pass is described as including only 250 minutes of calling.

Verizon customers with one of their Unlimited plans ($65/mo.) get data, calls, and text in Canada and Mexico as part of that service. Otherwise, it’s $6/day for either Canada or Mexico.

With Unlimited Ultimate, you get a similar-but-worse deal than the $100/month TravelPass benefits: 15 GB per month before 3G throttling, plus unlimited texting and calls. I’m unclear if layering a day pass on top would change that—probably—but at that point, you should consider an eSIM data service provider.

Verizon’s pay-as-you-go rates are set country by country, but my spot check shows they are the same as AT&T: $2.05/MB, thus $2,050/GB.

Find a data eSIM alternative

If you need more than the included amounts with service or find the day pass or other extended usage rates a bit high as you add them up, this is where roaming eSIM providers come in. While there are many companies you can purchases these from, a few appear frequently across reviews and testing; I’ve used one of them.

For the purposes of apples-to-apples comparison, I’m listing the price for European coverage, which typically covers roughly 40 countries, including the UK and all EU nations. For specific countries or other parts of the world, prices tend to be comparably proportional to Europe. I’m also looking at the best data and dollar combinations relative to the cost of using carrier day passes or upgrading service.

• Airalo: The company has what it calls a Eurolink eSIM, which has two sweet spots of unlimited data for 10 days for $35 (up to 3 GB per day before throttling) or 20 GB of data across 30 days for $49. I’ve used them on two different trips, and topping up service while still underway was a breeze via their app.
• aloSIM: aloSIM’s European eSIM packages include 15-day unlimited usage for $35 (up to 1.5 GB per day before throttling) or $37 for 10 GB across 30 days.
• Holafly: Holafly only offers unlimited data plans in Europe, with 10 days costing $36.90; a 30-day plan is $74.90. No specific daily limited are noted: “Some carriers may reserve the right to apply a Fair Usage Policy.” You can also share up to 1 GB/day as a mobile hotspot.
• Saily: Get unlimited usage in Europe over 10 days for $35.99 with a maximum of 5 GB per day at full speed and then 1 Mbps thereafter. A 30-day plan with 10 GB is $35.99 as well.

The decision tree

Carrier options used to be so terrible and expensive that it seemed silly to discuss them. Now, with the options described above, you might be able to use included service or upgrade a line or your family to a higher tier plan for one month (if allowed with your service). Day passes could be very useful occasionally for a single day, but once you hit two or more days, there’s no reason to pick one over an eSIM data option.

However, don’t forget to figure in Wi-Fi hotspots. High-speed Internet service is often available at many locations even in mid-sized or small cities charging reasonable fees. If you’re in a hotel with uncapped service or in a rental home or with friends or family and know that they aren’t charged overages, that’s a great way to manage your high-usage uploads, too.

[Got a question for the column? You can email glenn@sixcolors.com or use /glenn in our subscriber-only Discord community.]

[Glenn Fleishman is a printing and comics historian, Jeopardy champion, and serial Kickstarterer. His latest books are Six Centuries of Type & Printing (Aperiodical LLC) and How Comics Are Made (Andrews McMeel Publishing).]

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