No, you cannot top up data since our Travel SIM cards are unlimited.

NOTE ABOUT THE TRAVEL 4G UNLIMITED SIM:

※To manage network resources, the Travel 4G Unlimited SIM is managed by a Fair Usage Policy (FUP). For this SIM card, unlimited data means you will not be disconnected based on your usage or the amount of data transferred.

We do our best to provide our customers with large amounts of data that they can comfortably use while in Japan. However, depending on the carrier’s decision, the overuse of mobile communication will affect the usage of other customers and may be deemed as irregular usage.

※The Travel 4G Unlimited SIM card does not support long-term video streaming, video-conferencing/calling for extended periods of time, or downloading large amounts of data. 

If you plan on using the SIM card for such purposes, please select the Travel 5G Unlimited SIM card instead. Please click here for further details: Is a 5G Network available for Travel physical SIM?