Best Unlimited data eSIMs for Japan | Everything you need to know in 2025

Landing in Japan for the first time is exciting – the neon glow of Shinjuku, the quiet temples in Kyoto, even the endless rows of vending machines that seem to sell everything under the sun.

Ahhh the memories! But I digress, we’re here to discuss Japan unlimited eSIMs, so let’s crack into it.

Why Choose an Unlimited Data eSIM in Japan

When you land in Japan, one of the first things you’ll notice is how much you rely on the internet. That’s where an unlimited data eSIM in Japan comes in. Instead of juggling WiFi hotspots or worrying about your allowance running out mid-trip, you just install a plan on your phone and get rolling. It’s the “flashpackers” way to stay online compared to fiddling with physical SIM cards that you can easily lose in your wallet or bag. If you’re curious about different plan types, I’ve put together a full guide to the best eSIM Japan options.

Benefits of Unlimited Internet for Japan Travel

The best part about using an unlimited eSIM for Japan travel is that you don’t need to worry about your data – just use and abuse baby. You don’t have to think twice about opening Google Maps every five minutes or streaming Spotify on full HD mode (it’s new, you should try it). Who wants to be checking their data balance on holiday - hell no. Unlimited internet makes travel life smoother, I personally love knowing I can scroll, post videos, or call home whenever I like without doing mental maths about how much data I’ve burned through.

Unlimited eSIM vs Unlimited SIM Japan

Here’s where things get interesting. A Japan eSIM with unlimited data is entirely digital, meaning you scan a QR code and boom - you’re connected. No fiddly little pieces of plastic, no hunting for SIM ejector pins in your bag. Traditional unlimited SIM cards in Japan still work fine, but they usually mean lining up at the airport or hunting down a shop. Plus, swapping out your main SIM can be annoying if you still need your regular number active. With an unlimited eSIM you just add it alongside your current plan and switch it on when you land. That convenience is a win every time.

***If you want to compare which providers actually deliver good coverage and speed, check out my breakdown of the best eSIM Japan picks.

How Unlimited eSIMs Work in Japan

The beauty of an unlimited eSIM in Japan is how easy it makes life for travellers, everything happens digitally. You purchase a plan, get your eSIM delivered instantly to your inbox or app, and install it in just a few steps. Once it’s installed, your phone essentially thinks it’s running a local Japanese SIM, which means you get the same benefits without the hassle. It’s modern tech that feels like a little travel cheat code, and honestly, once you try it you’ll never want to go back.

Setting Up a Japan eSIM with Unlimited Data

Getting set up with a Japan eSIM with unlimited data is easier than most people expect. After you buy your plan you’ll get a QR code by email, which you can scan to install your eSIM - you can even do this before you leave home. If you prefer, and you’ve bought your plan through ZenSim, you can log into the ZenSim app and install it with just a tap on newer iOS devices. Manual installation is also an option if you like to keep things old school. Once installed, that’s it. When you land, you’ll just need to check a couple of basic settings which we email you (twice, just to be safe). For more detail, you can always refer to our eSIM troubleshooting guide for extra peace of mind.

Compatible Devices for Unlimited eSIM Japan

Not every device plays nicely with eSIMs, so it’s worth double-checking before you buy. Most recent iPhones from the iPhone XS and above are fully compatible, and many Android flagships like the Google Pixel 4 onwards, Samsung Galaxy S20 series and newer, and a growing list of tablets support eSIM too. The good news is that more devices are joining the club every year, so if you’ve upgraded recently there’s a good chance you’re covered. We keep an updated eSIM compatibility checker on our site so you can confirm in seconds whether your phone or tablet works with an unlimited eSIM in Japan.

Best Unlimited eSIMs for Japan Travel

Here’s a quick breakdown of the most popular unlimited eSIM options for Japan:

ZenSim

ZenSim offers unlimited hot spotting and has strong reviews (4.9/5 on ProductReview). Speeds slow after 3GB a day but reset at midnight which is plenty of data. ZenSim have the best value of the lineup.

Price: 30 day plan - A$105 ($66 USD)

Holafly

Holafly is a well-known global brand with flexible day-based plans which is cool. Hot spotting is limited to 500MB per day and speeds are subject to a “fair use policy”. TrustPilot rating 4.5/5.

Price: 30 day plan - A$117 ($74.90 USD)

Ubigi

Ubigi is priced similarly to ZenSim and is also a popular choice for the region. Marketed as unlimited, but speeds drop to 1Mbps after 60GB total use, which works out closer to 2GB a day. TrustPilot rating 4.1/5 on the lower end of the comparisons.

Price: 30 day plan - A$105 ($66 USD)

Airalo

Airalo is a common pick for short trips but only offers a 10 day unlimited plan for Japan. Some travellers report patchy service (see this Reddit thread) but including since they’re a popular choice in general.

Price: Varies by length (10 day only)

Costs of Unlimited Data eSIMs in Japan

Unlimited data eSIMs in Japan vary a fair bit depending on the provider and how they define “unlimited”. Some offer genuine daily resets, others work more like big data bundles with caps hidden in the fine print. Here’s how the pricing breaks down if you look at 30 day plans and what to expect when providers say unlimited.

Unlimited eSIM Japan Pricing Comparison

Looking at the main providers, the average price for a 30 day unlimited eSIM Japan plan falls between A$105 and A$117.

• ZenSim – A$105 ($66 USD) for 30 days (about A$3.50 per day)
• Holafly – A$117 ($74.90 USD) for 30 days (about A$3.90 per day)
• Ubigi – A$105 ($66 USD) for 30 days (about A$3.50 per day)
• Airalo – 10 day unlimited plan, price varies, not ideal for longer stays

On average, you’re looking at around A$3.50 to A$4 per day for unlimited data in Japan, which is pretty reasonable compared to roaming charges from home carriers.

Data Speed and Fair Usage Policies

The catch with unlimited internet in Japan is how providers define it. With ZenSim, you get full-speed data until 3GB per day, then speeds are reduced until midnight when it resets. Ubigi works differently, giving you up to 60GB total, after which speeds are capped at 1Mbps, so it feels more like a large bundle than true unlimited. Holafly references a “fair use policy” without stating clear limits, which can be confusing, I have scoured Reddit for anecdotal evidence of their limits which vary but Holafly keep it very secret.

In practice, “unlimited” usually means enough high-speed data for streaming, navigation, and daily use, but expect speed reductions if you hammer through hours of Netflix or big downloads. It’s worth reading the fine print so you know exactly what kind of unlimited you’re getting though I’ve done that for you in this article 

Where to Buy a Japan eSIM with Unlimited Data

One of the best parts about using an eSIM is how simple it is to buy. You don’t have to wait until you’re at the airport or track down a shop in Tokyo – you can get set up from your couch before you even pack your suitcase. That said, there are still physical SIM cards floating around Japan, but they’re slowly fading away as eSIM takes over.

Buying an Unlimited eSIM Before You Travel

The easiest option is to buy your unlimited eSIM online before you leave. Providers like ZenSim, Holafly, Ubigi, and Airalo all deliver a QR code instantly after purchase. You just scan it and you’re ready to go. I always recommend checking reviews and comparing details like price, hot spotting limits, and fair use policies before deciding – all those small things can make a big difference once you’re on the ground.

Tip: Before buying, check the fine print especially around usage limits and hot spotting

Getting an Unlimited SIM in Japan

Physical SIMs aren’t totally dead yet, and you’ll still see them at airport counters and electronics stores. But let’s be real – the latest iPhones don’t even have SIM card slots anymore, which tells you exactly where the industry is heading. If you’re still on the fence, take this as your nudge to switch. Installing an eSIM is ridiculously easy, no fiddly trays or tiny bits of plastic to lose, and once you’ve done it you’ll wonder why you didn’t make the jump earlier. For Japan travel, I’d pick eSIM every time.

Final Thoughts – Is an Unlimited eSIM Worth It for Japan Travel?

If you’re heading to Japan, an unlimited eSIM is hands down the easiest way to stay connected. The pricing is fair– usually around A$3.50 to A$4 a day – which is a bargain compared to international roaming charges.

Sure, each provider has its own quirks with speed caps and fair use rules, but for most travellers the experience feels close to seamless. You can stream, navigate, and share your trip without second guessing how much data you’ve got left. For me, the convenience of scanning a QR code, activating in minutes, and having unlimited internet across Japan makes the choice an easy one. If you want a reliable option with unlimited hot spotting and strong reviews, I’d recommend checking out the ZenSim Japan plan as a solid place to start.