MobileSIM eSIM Data Plans for Japan

MobileSIM does not offer a truly unlimited data eSIM for Japan. The plans labelled “Japan Unlimited” give a fixed allowance of 3 GB per day and, after that limit is reached, the speed is reduced to 1000 kbps. For travellers who need a larger data supply, MobileSIM provides fixed‑data plans such as the 30‑day Japan Unlimited plan at 3 GB per day, the 100‑GB Asian plan for 180 days, or the 50‑GB Asian plans for 7–30 days. These options allow users to purchase a larger data amount and are often more cost‑effective for moderate to heavy data usage.

MobileSIM does not offer an eSIM plan for Japan that includes a phone number or SMS capability. Travelers who need a phone number or SMS will need to use a data‑only plan and can rely on VoIP applications such as WhatsApp, Telegram, or iMessage over the data connection. Some destinations may block or restrict specific VoIP services, so it is advisable to verify that the apps you plan to use are accessible in Japan before purchasing a MobileSIM plan.

MobileSIM offers 12 single‑country (Japan‑only) plans and 22 multi‑country plans that include Japan. The plans are priced between $2.34 and $89 and provide data from 200 MB up to 100 GB over 3 to 180 days. Plans are split into daily data‑cap options, which limit the amount of data you can use each day, and fixed data‑cap options, which allocate a set amount of data for the entire validity period.