SIM & eSIM: Avoiding Scams in Japan

eSIM from 1,00 USD · 100 MB. Networks: KDDI/au (5G), NTT docomo (4G), NTT docomo (5G), Rakuten Mobile (5G), SoftBank (5G).

Where to buy a SIM or eSIM safely in Japan

Real risks

• Street vendors / hawkers: SIMs may be stolen, limited or fail to activate. Hard to get a refund.
• Airport SIM shops: generally safe but typically 2–3× city prices.
• "Pre-activated" SIM offers: if someone offers to activate the SIM for you, they could access your data or link your number to another account.

Safe options

• Official carrier store: the most reliable option for a local SIM. Bring your passport.
• Electronics / phone chains: usually have clearer pricing and proper receipts.
• eSIM online (before you travel): avoids all physical risk. Buy with a card from home, receive the QR by email, activate when you're ready.

Quick checklist: stay online without surprises

The make-or-break moment is often the first 30 minutes after landing: maps, transport, messages. Install your eSIM on Wi‑Fi before you travel and switch mobile data to the eSIM when you arrive. That way you're not dependent on airport Wi‑Fi and you avoid accidental roaming charges.

For typical use (maps + messaging + light social media), 1–3 GB per week is often enough. If you tether for a laptop, take video calls, or stream daily, aim for 10 GB+ or a plan with fair-use throttling instead of a hard cut-off.

• Networks: KDDI/au (5G), NTT docomo (4G), NTT docomo (5G), Rakuten Mobile (5G), SoftBank (5G)
• Offline maps: download the area in Google Maps, Apple Maps, Yahoo! Japan Maps while you're on hotel Wi‑Fi.
• On the move: GO (taxi), S.RIDE, DiDi Japan + LINE, WhatsApp work well on low data — video and app updates are usually the real data drains.
• Common weak spots: Deep mountain areas (Nikko and Hakone lake districts) · Remote islands (Yakushima, Iriomote in Okinawa)
• City context: Tokyo: Excellent coverage; Metro LTE on most lines; dense buildings can blip indoors. · Osaka: Strong 4G/5G; Dotonbori and Namba districts well-covered.

Phone setup tip: keep your primary SIM active for calls/SMS (so 2FA codes can arrive), but turn off mobile data on that line. Set the eSIM as your data line — it prevents accidental roaming on the wrong SIM and keeps WhatsApp/banking flows more predictable.

Current eSIM plans (examples)

Examples from our database — availability and pricing can change.