Saily vs Ubigi for Japan

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Last checked: 2026-08-10

Short answer

For a short trip with light data needs, Saily may suit you better: its Japan page currently lists 1 GB for seven days at US$3.99. [source-saily-com-1]

For a longer, low-data stay, Ubigi may be the better fit: its Japan page currently lists a one-time 1 GB plan for US$4 valid for 30 days. [source-cellulardata-ubigi-com-2]

For heavier use, do not treat either provider’s “unlimited” option as unrestricted full-speed data. Saily says its Japan unlimited option provides 5 GB per day without a speed restriction, followed by unlimited data up to 1 Mbps. Ubigi’s monthly Japan unlimited page lists 60 GB at full speed, then data optimized to 2 Mbps for the rest of the plan. [source-saily-com-1] [source-cellulardata-ubigi-com-3]

Plan comparison at a glance

Saily for Japan

Saily’s Japan page lists 1 GB for 7 days at US$3.99, alongside 3 GB, 5 GB, 10 GB, and 20 GB options. [source-saily-com-1]

Its stated unlimited-plan terms are an important limitation for data-heavy travellers: Saily describes 5 GB per day without a speed restriction, then unlimited data up to 1 Mbps. [source-saily-com-1]

For activation on arrival, Saily says to enable both the eSIM and data roaming in device settings. [source-saily-com-1] Its iOS help centre documents app-based installation and a manual route, and says installation needs stable Wi-Fi. [source-support-saily-com-8]

Saily may fit: travellers who want the currently listed seven-day 1 GB option or need a smaller Japan plan for a short visit. [source-saily-com-1]

Potential drawback: the listed 1 GB plan has a much shorter validity period than Ubigi’s documented 30-day 1 GB plan. [source-saily-com-1] [source-cellulardata-ubigi-com-2]

Check Saily Japan eSIM options

Ubigi for Japan

Ubigi’s Japan page lists a one-time 1 GB plan for US$4 valid for 30 days. It identifies KDDI and NTT Docomo as Japan networks and states that data sharing is allowed. [source-cellulardata-ubigi-com-2]

For its monthly Japan unlimited option, Ubigi lists US$45 per month, 60 GB of full-speed data, and data optimized to 2 Mbps for the remainder of the plan. The page says this plan auto-renews and can be cancelled after three months. [source-cellulardata-ubigi-com-3]

Ubigi says SmartStart activates a plan automatically on arrival in a covered area when the Ubigi line is switched on. An unactivated plan expires six months after purchase. [source-cellulardata-ubigi-com-13]

Ubigi may fit: travellers who value a longer validity period for a small data allowance, or who expect to use a hotspot and want documented troubleshooting guidance. [source-cellulardata-ubigi-com-2] [source-cellulardata-ubigi-com-15]

Potential drawback: the documented monthly unlimited plan is an auto-renewing plan with a stated three-month cancellation condition, so read the current terms carefully before choosing it. [source-cellulardata-ubigi-com-3]

Check Ubigi Japan eSIM options

iPhone setup and hotspot notes

Before buying, check that your iPhone is unlocked. Apple says an unlocked iPhone shows “No SIM restrictions” beside Carrier Lock in Settings > General > About. [source-support-apple-com-5]

Apple says eSIM setup requires an internet connection and documents setup through Settings > Cellular > Set Up Cellular or Add eSIM. [source-support-apple-com-4]

Both providers publish iPhone hotspot instructions. Apple notes that Personal Hotspot uses the iPhone’s cellular-data connection and that availability can depend on the carrier and plan. [source-support-apple-com-7] Saily documents enabling Personal Hotspot after its eSIM is enabled. [source-support-saily-com-11] Ubigi documents enabling Personal Hotspot after selecting the Ubigi eSIM, and says that an unavailable hotspot may require APN registration before contacting Customer Service if the issue continues. [source-cellulardata-ubigi-com-15]

For provider-specific network troubleshooting, follow the provider’s current instructions rather than entering APN settings speculatively. Saily’s documented iOS network fix uses wbdata in the Mobile Data and LTE Setup APN fields for the specific issue described. [source-support-saily-com-10] Ubigi’s iPhone instructions specify mbb in the Cellular Data APN field and say to leave other fields empty. [source-cellulardata-ubigi-com-14]

Multi-country travel

Do not choose a winner for multi-country use without checking current plans for every destination. Ubigi says its installed eSIM can be used with services in more than 200 destinations, but that statement does not establish that a specific Japan plan includes multi-country coverage. [source-cellulardata-ubigi-com-12]

Verdict

Choose Saily if a currently listed 1 GB, seven-day Japan option matches a short trip. [source-saily-com-1]

Choose Ubigi if a currently listed 1 GB, 30-day option better matches a longer low-data stay. [source-cellulardata-ubigi-com-2]

For heavy data use, compare the full-speed allowance, reduced speed, validity, and renewal terms of the exact plan before purchase. [source-saily-com-1] [source-cellulardata-ubigi-com-3]

Methodology

This is a remote, research-based guide based on the cited official documentation and current published terms. We compared documented setup states, device instructions, roaming guidance, APN checkpoints, and provider-specific qualifications. We did not physically test, purchase, install, activate, or use any eSIM.