Even if your carrier already provides overseas data, it’s still worth buying one of these.

The best investment you can make for an overseas trip? Not jamming a week’s worth of clothes in a carry-on. Not paying hundreds for more legroom on the plane. It’s buying a local SIM or eSIM, specifically one that offers unlimited 5G data so you’re never disconnected.

In the past year, I’ve traveled to cover both Computex (in Taiwan) and IFA (in Germany), and on both occasions I purchased local SIM access for relative peanuts — about $30 or so for 7 to 10 days’ worth of data. Each plan I bought offered unlimited data on networks that were as good or better than what’s offered here in the United States.

Consider this: you’re likely going to be out and about, visiting museums, eating out at restaurants, streaming Netflix by the pool… Yes, you can use your hotel’s Wi-Fi, but only within range of the hotel. And with all the concerns about malicious actors lurking on public Wi-Fi, a dedicated cellular connection can be convenient and safe!

SIM and eSIM to the rescue

I opted for a local SIM over what my carrier already provides. T-Mobile (my wireless ISP) offers about 5GB of high-speed data when overseas, and your carrier may have a similar option. But if that limit is exceeded, throttling happens — not only does it slow down cellular data speeds, it also kicks you down to 4G or worse.

There’s a world of difference between the amount of data provided by a 4G network and how quick that data is. I’m willing to pay a little extra for the peace of mind in knowing that I’ll have all the data I want, when I want it! That’s thanks to local SIMs and eSIMs.

Mark Hachman / IDG

Mark Hachman / IDG

Mark Hachman / IDG

Most modern phones offer the option to use either a dedicated SIM card (physical) or an eSIM (digital). For the last several years, buying a new phone has generally meant swapping out your SIM card from the old phone to the new one. When you travel overseas, a local SIM provider gives you a different SIM card, which you then pop into your phone (and hold onto your personal SIM card for when you return home).

That process of popping a SIM in and out isn’t convenient, though. You have to make sure you don’t lose or break that tiny little card, and you need the dexterity to fiddle around with the SIM tray on your phone, get it open, insert your card, and close it again. That’s why eSIM is far more useful and what I recommend — if your phone supports it.

Why eSIM is better for travel

An eSIM (short for “embedded SIM”) essentially works by telling your phone to roam onto a local network with the authentication token to do so. When you buy an eSIM, the carrier sends data to your phone for activation, at which point you’re authorized to use their network.

What’s nice is that eSIMs work in conjunction with your home SIM — the eSIM can be programmed to access local data while your home SIM is still used for texts and calls. That’s especially useful if you rarely make phone calls but still want to send texts to friends and family.

When I visited Taiwan, I used a local SIM provider with my spare phone to be a dedicated “Taiwan” phone. And it worked! But having to walk around and hunt down a SIM provider after a 13-hour plane flight wasn’t exactly fun. That’s why when I visited Germany, I used this ByteSIM option that was about $30 for unlimited 5G data.

Picking the right eSIM provider does take a bit of research. Our sister site TechAdvisor recommends Saily, an app that serves as a front door to eSIM plans around the world. And if there’s a gotcha, it’s this: eSIM plans are activated in different ways. Some activate immediately (so your available time begins counting down as soon as the purchase is completed), others only kick in after you “redeem” the eSIM. The best ones only activate after your phone successfully connects to their network.

I particularly liked how ByteSIM advised me of what speeds to expect: I did get about 180Mbps on Germany’s Telekom network, and the SIM roamed freely between it and its competitors.

I also noticed an unexpected benefit: if you’re traveling in Europe, websites recognize you as an EU “citizen” and offer to clear your cookies. Hurray for EU privacy laws!

So, think about this the next time you’re traveling abroad: if you’re already going to spend thousands of dollars on airfare, hotels, meals, and activities, isn’t it worth spending just a few more bucks on a good foreign SIM or eSIM? Honestly, it’s the best travel investment you can make.

Further reading: Essential travel gadgets for your next trip