Ubigi eSIM Review for Japan 2026: NTT Docomo Network

Ubigi Overview

Ubigi is owned by Transatel, a subsidiary of NTT Group — the same company that operates NTT Docomo, Japan's largest mobile carrier. This gives Ubigi a unique advantage for Japan coverage.

Japan Plans & Pricing

• 3GB / 30 days: ~$9
• 10GB / 30 days: ~$19
• 50GB / 30 days: ~$49
• Unlimited / daily: Available through app

Ubigi's pricing is competitive, and their 3GB plan is one of the cheapest quality options available.

Network & Coverage

In our speed tests, Ubigi averaged 82 Mbps download and had the fewest signal drops on the Shinkansen and in rural areas.

Ubigi uses the NTT Docomo network exclusively. This is significant because:

• Docomo has the best nationwide coverage in Japan
• Excellent in rural areas, mountains, and smaller towns
• Strong performance on all Shinkansen routes, including northern lines
• Reliable even in Hokkaido, Okinawa's outer islands, and remote onsen towns

If your trip goes beyond major cities, Ubigi is one of the safest choices.

Pros

• NTT Docomo network — best rural coverage
• Competitive pricing
• Backed by NTT Group (reliability guarantee)
• Good for extended stays (30-day plans)
• Top-up through the app

Cons

• App experience is functional but not as polished as Airalo
• No 5G on most plans
• Setup requires QR code scanning (no direct app install)
• Fewer plan tier options than some competitors

Who Should Choose Ubigi?

• Travelers visiting rural Japan (Hokkaido, Tohoku, Shikoku)
• Those prioritizing network reliability over app experience
• Budget travelers who want Docomo-quality coverage at a reasonable price
• Long-stay visitors (30-day plans)

Real-World: Ubigi on a 10-Day Hokkaido Road Trip

The real test for an eSIM isn't Tokyo. It's rural Japan. Here's Ubigi on the Docomo network across Hokkaido.

Haneda Airport, Day 1:

Bought the 10GB / 30-day plan ($19) on the Ubigi website before the trip. Setup was less seamless than Airalo — needed to scan a QR code emailed to me, then manually configure the APN. Took about 5 minutes with the instructions. Not hard, but not one-tap either.

Sapporo, Days 1–2:

Full bars, 50–70 Mbps. No different from any other provider in a major city. Used Google Maps, booked restaurants on Hot Pepper, checked Navitime for JR schedules.

Furano & Biei (rural center), Days 3–4:

This is where Docomo earns its reputation. Driving through lavender fields and patchwork hills — full signal the entire time. Google Maps navigation never hiccupped. Tried the same route friend's au-based eSIM: dropped to 1 bar multiple times.

Shiretoko Peninsula, Day 5:

Japan's wildest national park. Narrow roads, dense forest, no buildings for kilometers. Still had 3G signal along the main road and at the Shiretoko Five Lakes parking area. Lost signal only on the hiking trail deep in the forest. No other provider would have been better.

Asahikawa → Hakodate by train, Days 7–8:

The JR limited express cuts through mountains and coastline. Signal fluctuated between 4G and 3G but never dropped completely. Streamed Spotify for 3 hours. Used 800 MB that day.

Total data used: 6.2 GB over 10 days. Plenty left for a longer stay.

Verdict: If your trip goes beyond Tokyo–Osaka–Kyoto, Ubigi on Docomo is the safest bet. The setup is slightly clunkier, but the coverage is unmatched.

Get Ubigi for Your Japan Trip

Ubigi is the go-to choice for travelers heading beyond major cities. Set up your eSIM before you fly.

Visit Ubigi — Japan eSIM Plans →

Want to compare options first?

• Ubigi vs Airalo: Speed Test Results
• Best eSIM for First-Time Japan Visitors
• Japan Mobile Network Coverage Guide
• See all Ubigi plans →
• Compare all 317+ plans →

Rating

| Category | Score |

|----------|-------|

| Pricing | 4/5 |

| Coverage | 5/5 |

| App Experience | 3/5 |

| Customer Support | 3.5/5 |

| Overall | 4/5 |