eSIM vs Roaming: I Compared the Real Costs (2026)

I got back from a week in Tokyo and checked my phone bill. $98 in roaming charges. For one week. I didn't even use that much data — mostly maps and messaging.

That's when I looked into how roaming actually works. Turns out, your carrier connects to the exact same local networks that an eSIM uses. The only difference? Your carrier adds a 500-1000% markup on top.

So I ran the numbers for five popular destinations.

Here's what I found when comparing a 7-day trip:

Destination | eSIM Net | Carrier Roaming | You Save France | $2.99 (1GB) | $70 (T-Mobile) | $67 USA | $5.99 (1GB) | $84 (AT&T) | $78 Japan | $3.99 (3GB) | $98 (Verizon) | $94 UK | $4.99 (3GB) | $42 (Vodafone) | $37 Thailand | $3.99 (1GB) | $70 (T-Mobile) | $66

Average savings per trip: $68. Traveling as a couple? That's $136. Family of four? $272 — enough for a nice dinner and a day tour.

No. This is the part that surprised me most.

eSIMs connect to the same towers your roaming plan uses. T-Mobile in France? They're renting capacity from Orange. Your eSIM? Also on Orange. Same network, same speeds.

In fact, eSIM users sometimes get better speeds because they're on a local data plan — not a throttled roaming connection. T-Mobile's "free" international roaming gives you 2G speeds. That's 128kbps. You can't even load a photo at that speed.

1. Buy an eSIM at esimnet.org before your trip 2. Scan the QR code — it installs next to your regular SIM 3. Turn off your carrier's data roaming in settings 4. Land at your destination, switch to eSIM data

Your phone number still works for calls and texts on your regular SIM. The eSIM handles data. You get both.