Saily
20 GB · 30 days
$24.99$1.25/GB
See this planA 30 days trip needs a plan that will not expire before your flight home. Among the plans published today, Saily offers the best balance for 30 days ($24.99), while Saily is the lowest price at $24.99.
Updated September 24, 2026Prices checked September 24, 2026
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20 GB · 30 days
$24.99$1.25/GB
See this planUnlimited · 30 days
$66.00
See this plan20 GB · 30 days
$24.99$1.25/GB
See this planPlan shown: the cheapest plan of each provider that covers at least 30 days and 15 GB. Tap a column header to sort.
| Provider | Data | Validity | Price | Price/GB | Japanese network | 5G | Hotspot | Score | CTA |
|---|---|---|---|---|---|---|---|---|---|
| Saily | 20 GB | 30 days | $24.99 | $1.25/GB | KDDI/SoftBank | Yes | Yes | 9.8 | View plan |
| Airalo | 20 GB | 30 days | $25.00 | $1.25/GB | SoftBank/KDDI | Yes | Not stated | 9.2 | View plan |
| Yesim | 20 GB | 30 days | $29.76 | $1.49/GB | KDDI | Yes | Yes | 8.5 | View plan |
| Holafly | Unlimited | 30 days | $73.90 | — | KDDI/SoftBank | Yes | Yes | 6.4 | View plan |
| Drimsim | 15 GB | Pay as you go | $186.68 | $12.45/GB | Not published | Not stated | Not stated | 3.2 | View plan |
Plan for this page: 20 GB · 30 days
Plan for this page: 20 GB · 30 days
Plan for this page: 20 GB · 30 days
Plan for this page: Unlimited · 30 days
Plan for this page: 15 GB · Pay as you go
A 30 days trip is long enough for data use to drift upwards: more photos, video calls home, maybe some remote work. With the assumption used on this site the minimum is about 15 GB, but heavy users should check the estimator below before buying.
On longer stays unlimited plans become more attractive, because the price per day falls with the length. Yesim currently offers the cheapest unlimited plan lasting the whole trip, at $66.00. Check whether a daily fair-use limit applies.
Some providers let you top up the same eSIM instead of buying a new one, which is handy if you run out before the end. The provider reviews linked below say which ones publish a top-up option.
Every price on this page is the one published for Japan on the date shown at the top, in US dollars as the provider displays it; the final amount is the one shown at the provider’s checkout.
Pick your trip length and how you use your phone. The assumptions are visible and editable.
Buy the plan before you leave and keep the QR code or the app handy.
Install the eSIM at home on Wi-Fi. Most plans only start the validity period once the eSIM connects in Japan.
On landing, switch the eSIM on for mobile data and keep your home SIM for calls and texts if you need them.
Turn on data roaming for the eSIM line, then check that the phone shows a Japanese network.
Your phone must be carrier-unlocked and eSIM-compatible. Check this in your phone settings before you buy.
With this site’s assumptions a light user needs about 0.3 GB a day and a medium user about 0.8 GB. For 30 days the plans shown here carry at least 15 GB; use the estimator to adjust.
Among the plans that last at least 30 days and cover at least 15 GB, the cheapest is Saily at $24.99. Prices were checked on September 24, 2026.
On today’s published prices Saily ranks first for 30 days, at $24.99. The score weighs price, Japanese network, hotspot and options; the formula is explained under the ranking.
Many unlimited plans apply a fair-use rule and slow the speed after a daily threshold. Read the plan conditions on the provider’s page; Yesim currently has the cheapest unlimited option here at $66.00.
Yes, and it is the easiest option: scan the QR code or use the provider’s app on Wi-Fi before departure. Most plans only start counting days when the eSIM first connects in Japan.
A pocket Wi-Fi shares one connection with several devices but must be collected, charged and returned. An eSIM lives in your phone, so there is nothing to carry or give back.
We compare the plans each provider publishes for Japan. We do not rank on personal testing or user reviews. For each provider we take the cheapest plan that covers the need of this page, then compute a score out of 10:
At equal score, providers we have a partner link with are listed first. Prices change often, so check the final price on the provider’s site.