Roaming with Verizon, AT&T, or T-Mobile in Japan vs. Getting a Local eSIM

If you're heading to Japan and wondering whether your U.S. phone plan will work there, you're not alone. We hear this question a lot—especially from travelers using Verizon, AT&T, or T-Mobile. After all, these carriers all promote international roaming. Your phone says it can work abroad. So why do so many people still recommend getting a Japanese eSIM instead?

The answer comes down to three things: cost, speed, and reliability.

And no—you don’t need to be a tech person to care about this. You just want your phone to work smoothly while you’re overseas. Totally fair.

What It's Really Like to Use Roaming in Japan

Let’s start with the basics: yes, your Verizon, AT&T, or T-Mobile phone will technically work in Japan. Your phone connects to a local Japanese network—usually SoftBank, au, or docomo—through roaming.

But here’s what you might not realize until you’re already there:

• It usually costs extra. Verizon’s TravelPass is $12/day. AT&T charges $12/day, too. T-Mobile’s Magenta Plan gives you basic data, but it’s often slow unless you pay for a speed upgrade.
• You might not get full-speed access. Since you're roaming, you're not always treated like a local customer on the Japanese network. That means your speeds can get deprioritized during busy times—especially in train stations or tourist hotspots.
• It is convenient. The main benefit of roaming is that you don’t have to set anything up. Your phone just connects, and you’re good to go.

So yes—it works. But depending on how long you’re staying, you could end up spending $70 to $300+ just to stay connected. And you might still find yourself waiting for Google Maps to load.

How a Local Japanese eSIM Compares

eSIMs used to sound complicated, but they’re actually very easy to use—especially with newer iPhones or Android models.

A local Japan eSIM connects you directly to a Japanese network, without going through international roaming. You just scan a QR code and you're online.

Here’s why many travelers (even non-techy ones) are choosing Japanese eSIMs:

• Much cheaper: A 4-week plan can cost as little as $30 to $55 total(v.s. $336 in roaming), depending on how much data you need.
• Faster and more stable: Since you’re on a local network, you get local-level priority and speed. No rerouting or slowdowns during peak times.
• No physical SIM card: Nothing to lose, nothing to swap. You just scan a QR code, follow a few setup steps, and you’re done.
• Great for newer phones: Devices like the iPhone 15 don’t even have a physical SIM slot in the U.S. anymore, so eSIM is the way to go.

Here’s a general idea of Japan eSIM prices (using CDJapan Rental as an example):

• 30GB / 8 days: around $22
• 50GB / 31 days: around $34
• 135GB / 91 days: around $75
• Unlimited / 10 days: around $35
• Unlimited / 31 days: around $55

Of course, it’s not perfect for everyone. Some locked phones from U.S. carriers might not accept other eSIMs, and you do need to follow a few steps to set it up (usually takes about 5 minutes).

So Which Option Is Better for You?

Here’s a general rule of thumb we like to share:

Roaming is fine if...

• You’re only in Japan for a few days
• Your company is covering the cost
• You really don’t want to touch any settings

But we usually recommend a local Japan eSIM if...

• You’re traveling for a week or more
• You want faster, more reliable data
• You’re traveling with others and want everyone to have their own connection

A lot of travelers say they planned to use roaming, but switched to an eSIM after a few days because roaming was either too slow or too expensive. Getting the eSIM first saves that frustration.

Final Thoughts: Roaming or eSIM in Japan?

If you're staying a few days in Japan and want zero setup, roaming will work—just be ready for the daily fee.

But if you care about cost, speed, or just want a smoother trip overall, a local eSIM is a smart move. Especially for iPhone 15 and newer users, it’s the most seamless way to stay connected in Japan.

We recommend buying your Japan eSIM online before your trip, so you can activate it the moment you land. CDJapan Rental offers eSIM plans that run on docomo, one of Japan’s most reliable networks—perfect for travelers who want great coverage and simple setup.

Browse Japan eSIM Plans >