Airalo vs Saily for Japan: which eSIM should you buy?

Airalo and Saily are two of the most popular travel eSIMs for Japan, and on paper they look almost identical: both run on Japan's big networks, both sell data-only plans you install before you fly, and both have unlimited options. The differences are in the details – how much full-speed data the "unlimited" plans really give you, which trip lengths are sold, and the price for the plan you actually need.

Quick answer (prices as of Airalo 2026-10-13, Saily 2026-10-12)

• Cheapest way to get online: Saily 1 GB / 7 days for US$3.99.
• Heavy users (video, hotspot, remote work): Saily's unlimited plans give 5 GB per day at full speed before slowing, versus 3 GB per day on Airalo's – worth it if you stream or share your connection.
• Light users on a short trip: a small fixed-data plan is far cheaper than unlimited. Airalo starts US$4.00, Saily starts US$3.99.

Price comparison: Airalo vs Saily in Japan

The table below comes from our price database (last checked: Airalo 2026-10-13, Saily 2026-10-12). "Unlimited" rows compare the same number of days; data rows show the cheapest plan of that size and how long it lasts.

A few things stand out:

• Unlimited for a week costs almost the same on both: Airalo US$26.50 vs Saily US$26.99 for 7 days.
• Unlimited starts at different lengths. Airalo's Japan unlimited plans start at 3 days, so it's the one to pick for a short stopover. Saily's start at 5 days and come in 5, 7, 10, 15, 20, 25 and 30 days.
• Small fixed-data plans differ in validity, not just size. Saily's small plans tend to last longer (for example 1 GB for 7 days), while Airalo also sells short 3-day packs. If your trip is long but your usage is light, the validity matters more than the gigabytes.

Networks and coverage

Both providers use the same two Japanese networks:

• Airalo (operator "Moshi Moshi"): SoftBank and KDDI, 5G where available. Airalo says it covers all of Japan, including Okinawa and Hokkaido.
• Saily: KDDI and SoftBank, 4G/LTE and 5G where available.

In practice you should get similar coverage with either: strong in Tokyo, Osaka, Kyoto and along the Shinkansen lines, patchier deep in the mountains (Japanese Alps, rural Tohoku). Since both use the same networks, coverage is not a reason to pick one over the other.

"Unlimited" is not the same on both

This is the biggest real difference, and both providers state it on their own Japan pages:

	Airalo unlimited (Japan)	Saily unlimited (Japan)
Full-speed data per day	3 GB	5 GB
After that	slowed to 1 Mbps until the next day	slowed to up to 1 Mbps

(Figures stated by the providers, checked 2026-10-02.)

1 Mbps is enough for messaging, maps and music, but not for smooth HD video or video calls. So:

• If you mostly use maps, LINE/WhatsApp, Instagram and some browsing, 3 GB a day is plenty and either provider works.
• If you stream, upload lots of video, work remotely or share a hotspot with family, Saily's 5 GB daily allowance gives you more headroom for roughly the same price.

Which one for your trip?

Short city break (3–5 days), light use. Pick the cheapest small plan that covers your days. Right now that's Saily 1 GB / 7 days for US$3.99. Use hotel and café Wi-Fi for anything heavy.

One week, normal use (maps, social, some video). A 5 GB plan is usually enough for a week of normal use – the cheapest 5 GB option lasting a week or more is Airalo 5 GB / 7 days for US$10.00. If you'd rather not think about it, compare the 7-day unlimited rows above.

Two weeks or more. Fixed-data plans are often the best value, for example Airalo 10 GB / 15 days for US$17.50 for 10 GB+. For heavy users, compare the 15-day unlimited prices – Airalo US$48.00, Saily US$48.99.

Travelling as a family and sharing a hotspot. When several phones share one connection, a higher daily full-speed allowance matters more. Check the provider's plan details to confirm hotspot sharing before you buy.

Topping up and activation

• Validity start: Airalo's Japan plans start counting when the eSIM first connects to a network; Saily says its plans activate automatically when you arrive. Either way you can install at home before you fly without losing days.
• Topping up: both let you add data in their app if you run low. Saily also offers an optional auto top-up.
• No Japanese phone number: both are data-only. Your normal number stays on your physical SIM (roaming charges from your home carrier may apply to calls and SMS), and WhatsApp, LINE and iMessage keep working over the eSIM's data.

How to install (both apps work the same way)

1. Check your phone supports eSIM and is not carrier-locked.
2. Buy the plan in the provider's app or website and tap Install eSIM (or scan the QR code) while on Wi-Fi at home.
3. Label the new line (e.g. "Japan") and keep your main SIM on for calls/SMS if you want them.
4. When you land: set mobile data to the Japan eSIM and turn data roaming on for that eSIM line (not your home SIM).
5. If you get no data, toggle airplane mode once and check the APN in the provider's install guide.

Bottom line

• Want the lowest price for light use? Compare the small data plans – today the cheapest is Saily 1 GB / 7 days for US$3.99.
• Want unlimited without worrying about slowdowns? Saily's 5 GB/day full-speed allowance beats Airalo's 3 GB/day at nearly the same weekly price.
• Want more Japan-specific trip lengths and short top-up-able packs? Airalo's range is broader on fixed data.

See every Japan plan from both providers on one page: Japan eSIM price comparison, or read our Best eSIM for Japan guide.

FAQ

Is Airalo or Saily cheaper for Japan?

It depends on the plan. As of Airalo 2026-10-13, Saily 2026-10-12, Airalo starts at US$4.00 and Saily at US$3.99. For 7 days of unlimited data Airalo costs US$26.50 and Saily US$26.99.

Which networks do Airalo and Saily use in Japan?

Both use SoftBank and KDDI (au), with 5G in some areas.

Are Airalo and Saily unlimited plans really unlimited in Japan?

Data is unlimited but full speed is capped per day: Airalo slows to 1 Mbps after 3 GB a day, Saily after 5 GB a day.

Can I use Airalo or Saily as a hotspot in Japan?

Hotspot sharing follows each provider's own plan details. If you need it, check the plan details on the provider's website before you buy.

Do Airalo or Saily give me a Japanese phone number?

No, the standard plans are data-only. You can still use WhatsApp, LINE and iMessage, and keep your home number active on your physical SIM.

When should I install the eSIM for Japan?

Install it at home on Wi-Fi a day or two before your flight. Plans start counting when they first connect in Japan, so you won't lose days.