Japan mobile data: roaming, eSIM and shared Wi-Fi limits

Regular prices checked on 9 October 2026 are KRW 29,000 for baro 3GB and KRW 3,300 per rental day for KT Japan Egg, including VAT. Five days from collection through return cost KRW 16,500 for the Egg. Allowances and calling features differ, so the prices do not describe identical services.

The baro figures exclude YT extra data, youth discounts and Club T Roaming's free refill. Do not price a youth offer as an ordinary baro 3GB plan. Sakura quotes its eSIM in JPY after you select a duration; no converted KRW price is included here.

Free baro calling means baro calls through the A. Phone app: calls to Korea, local calls and incoming calls, excluding outgoing calls to a third country. It does not make every call from the phone's standard dialler free.

baro's base 3GB covers the whole trip. A five-day trip does not turn it into 15GB. After the base allowance, data continues at up to 400kbps.

Sakura 3GB/day provides 3GB of high-speed data each day, then limits speed to 200kbps for that day. Hotspot use is supported, but additional connected devices do not multiply the phone's daily allowance.

KT Japan Egg shares 5GB per day across connected devices. It accepts up to five simultaneous devices and recommends no more than three for stable use. Travellers who split up cannot take the same Egg's Wi-Fi with each of them.

baro offers manual and automatic start types. With manual start, select a data allowance for each departure. Automatic start applies the selected allowance whenever you depart. Choose both the start type and allowance for this trip on the product page.

The day you install Sakura's 3GB/day eSIM counts as day one. Install after arriving in Japan, using a stable Wi-Fi connection. Buying it before departure and installing it on the phone are separate steps. The arrival-based start rule for Sakura Unlimited does not apply to this plan.

KT Egg rental is charged from collection through return, including days without use. Japan Egg is excluded from the official table's free-day offer for rentals of at least three days. No free day is deducted from the five-day example.

Sakura eSIM requires an eSIM-capable, carrier-unlocked phone supporting the relevant Japanese network bands. A phone name can cover different regional models. Compare the manufacturer's specifications for your exact model with the provider's compatibility checker. Wi-Fi access on a locked phone does not imply foreign eSIM compatibility.

The 3GB/day eSIM is tied to the phone on which it was first installed and cannot be transferred to another device. Installation needs internet access. If setup fails, use that plan's installation guide and support service. Keep Unlimited and 3GB/day deletion or reinstallation rules separate.

A data-only eSIM does not include calls on your Korean number. Following the provider's instructions, select the Japan eSIM as your data line and check that data roaming is off on your usual line. Calls and messages on the Korean number follow your existing carrier's terms.