Best trust record · largest daily cap · unnamed network
Saily in Japan
Saily has the best support record of anyone here by a wide margin and the biggest unlimited allowance sold for Japan. It also will not tell you whose network you are riding.
Every Saily Japan plan USD, checked September 2026
| Plan | Price | Per GB | Notes |
|---|---|---|---|
| 1GB / 7 days | $3.99 | $3.99 | GigSky's 1GB is $2.99 for the same week. |
| 3GB / 30 days | $7.99 | $2.66 | Fifty cents over GigSky, and twice the validity. |
| 5GB / 30 days | $10.99 | $2.20 | Yesim is $10.23 for the same size and window. |
| 10GB / 30 days | $17.99 | $1.80 | A penny under Airalo, $1.20 over GigSky. |
| 20GB / 30 days | $24.99 | $1.25 | Best 20GB with a full month. Airalo's is $24.00 for 15 days. |
| Unlimited / 5 days | $18.99 | $0.76¹ | 5GB a day at full speed, then throttled until midnight. Saily publishes the daily figure and not the throttled speed. ¹ Per-GB assumes you use the full 5GB every day. |
| Unlimited / 7 days | $28.99 | $0.83 | |
| Unlimited / 10 days | $34.99 | $0.70 | |
| Unlimited / 15 days | $48.99 | $0.65 | |
| Unlimited / 20 days | $59.99 | $0.60 | |
| Unlimited / 25 days | $65.99 | $0.53 | |
| Unlimited / 30 days | $71.99 | $0.48 |
Saily has the most granular unlimited ladder in Japan, seven lengths from five days to thirty. That is genuinely useful: a nine-day trip buys ten days rather than being pushed to fifteen. Prices in USD, checked September 4, 2026.
Saily sells the largest unlimited allowance in Japan 5GB a day
Nothing sold for Japan is actually unlimited. Every plan with the word on it is a daily allowance, and the question is only how big the allowance is and what happens when you cross it.
Saily's is 5GB per day. Airalo's is 3GB. GigSky's daily packs are 3.5GB. Nomad's is 2GB. Yesim and Ubigi do not publish a figure at all. So if you want the most full-speed data per day that anyone will commit to in writing for Japan, this is it, and it is not close.
Five gigabytes is a real amount. It is roughly five hours of 720p video, or a full working day of a tethered laptop with video calls, or every map, message and photo upload you can generate in a day plus a film in the evening. If you actually use it, thirty days works out at 48 cents a gigabyte, the cheapest full-speed data on this site by some distance.
The part Saily does not publish is what happens after 5GB. It says the connection is reduced until midnight and does not name a speed. Airalo prints 1 Mbps, which is the only number of that kind anyone in this comparison commits to.
If you are going to buy unlimited anyway, buy the largest published cap. Five gigabytes a day is the biggest number anyone will print for Japan.
See Saily unlimited plans Compare every capThe one thing Saily will not tell you which Japanese network
This site's central argument is that in Japan the carrier behind the eSIM decides whether your trip works, because Docomo, KDDI and SoftBank diverge sharply once you leave the cities. Saily publishes nothing about its Japanese partner.
Third-party listings on esimdb identify KDDI (au). Saily's own materials do not say it, and we are not going to launder a database entry into a network agreement by repeating it as fact. What we will report is the one substantive traveler complaint attached to it: reviewers on esimdb describe Saily's Japan traffic exiting through Hong Kong, which for at least one of them broke ChatGPT and other services that geolocate by exit address. That is a traveler report, not a published fact, and if you rely on a service that cares where your traffic appears to come from, it is worth knowing before you pay.
How much the missing network name costs you depends entirely on your route. On the Tokyo to Osaka corridor, close to nothing, because all three networks are strong there. In the Alps or rural Hokkaido, it is the difference between bars and no bars, and the fix is GigSky on Docomo rather than a different Saily plan.
The 4.7 across 30,542 reviews is the best record on this site and it is earned
Saily is run by Nord Security, the company behind NordVPN, and it shows in the support operation. Trustpilot 4.7 from 30,542 reviews as of September 4, 2026, with 83 per cent five-star and replies to 99 per cent of negative reviews, usually within a day.
For comparison, Airalo sits at 4.1 from 41,885, GigSky at 4.3 from 6,217 and Yesim at 4.3 from 2,942. The gap between 4.7 and 4.1 across tens of thousands of reviews is not noise.
Why this matters more than it looks: an eSIM fails at the worst possible moment, in the arrivals hall of a country where you cannot read the error message. The thing you are actually buying, once the prices are within a dollar of each other, is whether someone answers when it does not work.
Saily against the other three size by size
| Saily | GigSky | Airalo | Yesim | |
|---|---|---|---|---|
| 1GB | $3.99 / 7d | $2.99 / 7d | $4.00 / 3d | $4.30 / 30d |
| 5GB / 30 days | $10.99 | $10.29 | $11.00 | $10.23 |
| 10GB / 30 days | $17.99 | $16.79 | $18.00 | $18.59 |
| 20GB / 30 days | $24.99 | none | $25.00 | $28.82 |
| Unlimited, 30 days | $71.99 | none | $69.00 | $63.91 |
| Daily cap | 5GB/day | 3.5GB/day packs | 3GB/day, 1 Mbps after | not published |
| Japanese network | not published | Docomo + SoftBank | KDDI + SoftBank | KDDI + Docomo |
| Trustpilot | 4.7 · 30,542 | 4.3 · 6,217 | 4.1 · 41,885 | 4.3 · 2,942 |
Saily is never the cheapest and never far off. It wins 20GB over a full month by a cent, it wins the daily cap by a wide margin, and it wins the trust column outright. It loses the one column this site cares most about: it will not say whose network it is.
Buying and activating Saily four minutes
- Buy on the Saily website at home on wifi, and check the currency selector shows USD before comparing against the tables here.
- Pick the length honestly. Saily's unlimited ladder has seven rungs, so buy ten days for a nine-day trip rather than fifteen. Nobody else in this comparison lets you do that.
- Install the profile before you fly. It does not start counting until it connects in Japan.
- On landing: Saily line on for data, home line on for calls with data roaming off. If it will not attach, set network selection to manual and work through KDDI, SoftBank, Docomo, since Saily does not tell you which to expect. Full setup and fixes.
Buy Saily if, skip it if the short version
Buy it if
- You are hotspotting a laptop. The 5GB daily cap is the largest published in Japan and there is no separate hotspot ceiling.
- You want 20GB over a full thirty days, at $24.99.
- Your trip length is awkward. Seven unlimited lengths means you are not paying for days you will not use.
- Support matters to you. The 4.7 from 30,542 reviews is the best record on this site.
Skip it if
- Your route leaves the cities. Saily will not say which network it uses, and in the Alps or Hokkaido that is not a detail. Take GigSky on Docomo.
- You rely on services that geolocate by exit address. Reviewers report Saily's Japan traffic exiting via Hong Kong.
- You want the cheapest 10GB. GigSky is $1.20 less.
- You want an unlimited plan with the throttled speed printed. Only Airalo publishes that.
Saily Japan questions short answers
Which network does Saily use in Japan?
Saily does not publish it. Third-party listings identify KDDI (au), but Saily's own materials say nothing, and we are not going to state a network agreement the company itself will not confirm. If knowing matters to you, GigSky publishes NTT Docomo and SoftBank and Airalo publishes KDDI and SoftBank.
Is Saily unlimited really unlimited in Japan?
No, and Saily says so: 5GB per day at full speed, then reduced until midnight. That is the largest published daily allowance sold for Japan, larger than Airalo's 3GB and Nomad's 2GB. Saily does not publish the throttled speed, only that it is reduced.
Is Saily better than Airalo for Japan?
For hotspotting and long stays, yes: a bigger daily cap, a better trust score and a cheaper 20GB over thirty days. For a city trip, Airalo is a dollar cheaper at 20GB, publishes its network and prints both unlimited numbers. Neither has NTT Docomo.
How much is Saily unlimited for Japan?
From $18.99 for five days up to $71.99 for thirty, checked September 4, 2026, with seven lengths in between. All carry the same 5GB per day cap. At thirty days that is 48 cents per full-speed gigabyte if you use every day of it, which is the cheapest full-speed data in this comparison.
Is Saily trustworthy?
It has the best record of any brand on this site: Trustpilot 4.7 across 30,542 reviews as of September 4, 2026, 83 per cent five-star, replies to 99 per cent of negative reviews. It is run by Nord Security, the NordVPN company. The one substantive complaint we found is about Japan traffic exiting through Hong Kong, which is a routing quirk rather than a support failure.
5GB a day, published, the largest in Japan
Seven unlimited lengths from five days to thirty, a 20GB bucket at $24.99 over a full month, and the best support record on this site at 4.7 from 30,542 reviews. If your route leaves the cities, read the network section above first.
See Saily Japan plansSources & freshness: Plan prices from Saily's Japan listing via esimdb on September 4, 2026, in USD, before promo codes. The 5GB-a-day cap is Saily's own published figure. Saily publishes no Japanese network partner; the KDDI attribution is a third-party database entry and is labelled as such. The Hong Kong exit-address reports come from traveler reviews on esimdb and are traveler reports, not a tested finding. Trustpilot 4.7 across 30,542 reviews, checked September 4, 2026. How we test.