Written by Patrick Balfe
There are lots of “unlimited data” eSIMs for Japan, but not all are created equal. If you’re a digital nomad, business traveler, or chronically online, you might be looking for options with flexibility in terms of daily data limits. Here, we specifically compare semi-unlimited and truly unlimited Japan eSIMs, so that you can see which plan works best for you.
Not that fussed about caps? We also have a more general overview of eSIMs for tourists and short-term visitors to Japan, where we look at a broad range of different plans — covering everything from 3GB short-term options to 20GB deals and more. We also speed-test them, so definitely do check that guide out.
Quick comparison of unlimited and almost unlimited eSIMs
| Brand | Plan length | Price |
|---|---|---|
 | 1-31 days | USD $24 for 7 days. See plans. |
 | 7-30 days | USD $25 for 7 days. Fast 5G. 10% discount code – TOKYOCHEAPO. See plans. |
 | 4–30 days | USD $19 for 7 days. See plans |
 | 1-90 days | USD $26.50–$31.50 for 7 days. See plans |
 | 3-31 days | USD $8.99-$27.99 for 7 days. See plans. |
 | 5-180 days | USD $25 for 10 days |
 | 7-30 days | USD $20.75 for 7 days |
 | 1-30 days | USD $27.60 for 7 days |
Unlimited eSIMs with daily data caps
These are what we call “somelimited” plans — they are labelled “unlimited”, but come with some limits.
Ubigi Japan Unlimited eSIM
Special offer: Use the discount code TOKYOCHEAPO for 10% off
Ubigi is a global eSIM provider that covers more than 200 destinations. Their unlimited plans come in 7, 15, and 30-day options (they have a range of other plans, too).
While the plan is essentially unlimited, their fair-use policy says that your speeds will be capped if you happen to achieve the feat of using over 25GB on a 7-day, 30GB on a 15-day plan, or 60GB on a 30-day plan. That’s worth keeping in mind if you are planning on doing lots of online work or streaming.
What happens when you run out of data?
On all of the unlimited plans, your speeds will slow down to 2Mbps if you go over the relevant data limits. So, you won’t be cut off, but you will be throttled.
eSIM Japan Unlimited Data
Roaming on the nationwide KDDI network (read: very reliable), eSIM Japan’s Unlimited Data plans have daily caps ranging from Basic (1GB) and Pro (2GB). They also recently introduced a truly unlimited option, which we’ll get to later. You can choose from 3- to 30-day options.
Your plan starts once you connect to the local network, and daily usage resets at midnight. In terms of coverage, at the time of writing, the Unlimited Data plans had 4.5 stars from 2,539 ratings on the eSIM Japan website, with most users pointing to stable connectivity. Granted, it may not be unbiased, but it’s still strong.
What happens when you run out of data?
On all of the Basic and Pro plans, you’ll still have access to the internet with a download speed of 384Kbps once your daily limit is reached. So, once again, sluggish but not cut off. Top ups are available except for on the 15, 20, and 30-day plans.
Sakura Mobile
An established Japanese SIM and Wi-Fi provider popular with both short and long-term visitors, Sakura Mobile also has a line of eSIMs. A big selling point of Sakura’s Travel eSIMs is their flexibility.
Short-term eSIMs are available from 1 all the way up to 90 days with a combination of unlimited and fixed-data options.
If you’re after a semi-permanent option, Sakura offers long-term data-only and voice + data eSIMs at 5, 15, and 30GB per month.
It’s worth noting that their 4G-compatible unlimited plans have a 3GB daily usage cap. Their newer 5G-compatible unlimited eSIMS are touted as having no data caps, but they’re quite a bit more expensive; we’ll get into these below.
What happens when you run out of data?
The 4G-compatible unlimited plans have a 3GB per day limit, after which the data download speed is temporarily limited to 200Kbs and the high-speed 3GB is available again from midnight.
Sim Local
Sim Local has a range of 5G-compatible eSIMs with unlimited data plans running on the au network, and capped data plans running on the Docomo network. If you’re after unlimited data, they have affordable packages ranging from 4 to 30 days. Their unlimited plans come with a 10GB daily data cap.
What happens when you run out of data?
Sim Local’s website says that consistent daily use over 10GB may trigger KDDI Au’s Fair Use Policy. However, they’re unclear about how much your speeds may be capped or for how long.
Maya Mobile Japan Unlimited
This is a good all-round “somelimited” plan for those after a combination of unlimited or high daily data limits, cost performance, and speed. Running on the local KDDI au and Rakuten networks, Maya has good connectivity around the country with 4G/LTE and 5G speeds where available.
Compared to other providers, we found that Maya had exceptionally high trust ratings. For example, at the time of writing, Maya had 4.6 stars from 12,010 reviews on Trustpilot, with most users mentioning ease of set-up and use.
What happens when you run out of data?
Maya’s website mentions an Acceptable Use Policy for their unlimited data sims, but doesn’t specify exactly how they’re enforced — exactly when data caps are enforced and how long for may be at the discretion of local network providers.
Yesim eSIM Japan Unlimited
Another big name in unlimited data, Yesim also offers what appear to be truly unlimited 1–30-day plans. While their price points might be higher, Yesim is a good all-round option for those with a slightly higher budget when you factor in their high user ratings, 24/7 support, refund guarantee, and ease of installation.
What happens when you run out of data?
Their website says that download speeds on their unlimited sims may be limited in accordance with their network provider’s fair usage policy.
Truly unlimited eSIMs for Japan
Not willing to risk running out of data? Here are three unlimited plans with no daily data limits.
Mobal Japan Tourist eSIM
One of our favourite Japan eSIM providers, Mobal has also recently joined the truly unlimited market. Running on the KDDI network, their truly unlimited 5G-compatible eSIMs are available in 1 to 31-day options and offer consistently fast 5G speeds throughout the validity period.
In case you also want the option of voice calls, voice + data plans are also available in a variety of fixed-data plans. The Mobal website is easy to use and more transparent than some other providers, and if you’re a philanthropically minded traveler, the company’s profits are donated to charity.
eSIM Japan 5G Unlimited Max Data
eSIM Japan has entered the truly unlimited data realm with their 5G Unlimited Max Data plan. Also on the reliable KDDI network, the new offering supports 5G (where available) and offers free access to au Wi-Fi in places like Starbucks, Don Quijote, and Bic Camera. Plans run from 3 to 31 days on the Unlimited Max 5G plans.
Sakura Mobile 5G/4G Unlimited data eSIMs
Compared to their 4G Unlimited Data sims, which offer 3GB of high-speed data per day, Sakura’s newer 5G/4G Unlimited data eSIMs plans offer unlimited high-speed data. While being a bit on the pricier side, and only offering limited GBs on tethering, if fast speeds and truly unlimited data are important to you, they may be worth the extra yen.
eTravelSim Truly Unlimited Data eSIM for Japan
If you don’t mind the long name, eTravelSim is a great overall, truly unlimited option with options ranging from 7 to 30 days. Their website mentions that their plans run on the local KDDI au network with 5G, 4G, and LTE connectivity.
Note: Even the eSIM companies offering truly unlimited data plans are ultimately bound by the fair-use policy (FUP) of their network providers (Docomo, KDDI, etc). Although there are no daily data limits, providers may opt to institute their FUP by throttling your internet speeds until the next day if they deem that your data usage has been excessive. So just keep that in mind.
While we do our best to ensure everything is correct, information is subject to change. Prices are approximate. Post first published in May 2024. Last updated by Patrick Balfe in April 2026.
