JamboSim eSIM Data Plans for Japan

JamboSim does not provide a truly unlimited data eSIM for Japan. The plans that carry the “Unlimited” label in their names give 3GB of high‑speed data per day; after that limit the speed is throttled to about 1 Mbps. This fixed daily allowance is a hard cap, not a provision of unlimited data.

Instead, JamboSim offers fixed‑data plans that cover several gigabytes for a set number of days. For example, a 50GB plan valid for seven days or a 100GB plan valid for 180 days are available. These plans can be more cost‑effective for travelers who need a substantial amount of data within a fixed period.

JamboSim sells Japan eSIM plans that include a phone number and outbound SMS capability. The available plans range in data cap from 1GB to 20GB, in validity from 7 days up to 365 days, and in price from $11.99 USD to $105.99 USD. The phone numbers use the +1 dialing code, meaning they are not local Japanese numbers. Call and SMS features are outbound only: calls can be made and SMS can be sent, but incoming calls and messages are not supported.

If users need to be certain that a plan meets specific needs for voice or messaging, they should contact JamboSim directly to confirm the details.

JamboSim offers 13 single‑country data plans that are valid for Japan, and an additional 40 multi‑country plans that include Japan as part of their coverage network. These plans span a price range from about $1.99 up to roughly $106.00, and their data caps vary from a minimal 200 MB to an extensive 100 GB. Among the offerings you’ll find both daily data‑cap options—where a set amount of data is reused each day—and fixed‑data plans, which provide a lump sum of data that can be used at any pace during the validity period.