Staying in Japan for longer than two weeks? You won’t settle for more than a short-term tourist SIM or bulky pocket WiFi unit. Whether you’re a digital nomad, exchange student, or just sightseeing at a leisurely pace, you need a long-term reliable internet connection — and eSIMs are infinitely the easiest way to do it.

Unlike physical SIM cards or WiFi routers, eSIMs involve no shipping, no visits to the store, and no chance of losing small plastic chips. With a few clicks, you’re on one of Japan’s high-powered networks. If you want the best eSIM for Japan on an extended stay, this guide takes you through the best choices, personal experience included, to make the best decision.

What to Expect in a Long-Term eSIM for Japan

Let’s quickly summarize what actually counts while selecting an eSIM for a visit that lasts longer than two weeks:

Validity and Flexibility

Find eSIMs with a validity of 30 to 90 days, or plans that enable hassle-free top-ups or renewal. Short-term travel eSIMs (7 or 14 days) will do nothing but frustrate you.

Generous Data Plans

If you’re teleworking, streaming, browsing, or video chatting back home, you’ll need either unlimited data or at least a high-cap plan. Be wary of data throttling once you hit a tipping point.

Refill or Extension Options

Make sure the provider lets you recharge or extend your plan without having to re-install a new eSIM profile or go through technical hurdles.

Local Japanese Number (Optional)

Some providers provide an actual Japanese phone number — convenient for booking reservations, getting SMS verification, or even opening domestic accounts.

Reliable Networks

Select providers that route you through Japan’s highest-rated networks such as SoftBank, Docomo, or au. Signal and speed may vary based on where you are.

Seamless Setup and Support

Opt for a straightforward activation process, prompt customer support, and an easy-to-use app or website.

Best eSIM Options for Extended Japan Stay

After trying a few providers and digging into the most well-known eSIM services for extended Japan stays, here are the best ones:

1. Mobal – Best for Longer Stays & Local Number

If you need a solid connection and a local Japanese number, Mobal can’t be beaten. Mobal has long-term eSIM plans designed specifically for 30+ day travelers — ideal for students, remote workers, or slowpokes.

Mobal leverages Japan’s fastest and widest network, SoftBank, providing you with great coverage throughout the country. Plans last from 30 to 90 days and offer generous data limits or even unlimited. And a unique feature? You receive an authentic Japanese phone number, something no other eSIM providers can claim.

What’s especially nice about Mobal is their philanthropic mission — a portion of your purchase benefits education and development initiatives in Africa. That’s a win-win.

Pros:

• SoftBank network (speedy and solid)
• Local Japanese number included
• Long validity (up to 90 days)
• Extends well
• Easy setup with email instructions
• Profit portion donated to charity

Cons:

• Moderately greater expense than budget choices

Personal Note: I used Mobal on a 6-week business trip through Tokyo, Kyoto, and Sapporo. Installation was under 5 minutes. Speeds were great for Zoom calls, posting videos, and even mobile hotspotting my laptop. Having a Japanese number proved useful for making restaurant reservations and getting delivery SMS.

2. Airalo – Best Budget Option

For budget-conscious travelers wishing to remain connected, Airalo’s Japan eSIMs — in this case, the Asahinet Japan plan — are a good option. You can purchase data plans from 1GB to 20GB, and you can top up in the Airalo app itself.

Although Airalo does not provide a Japanese phone number, it is best for occasional users who mostly use messaging applications such as WhatsApp or LINE. The network performance is good (having a partnership with either NTT Docomo or KDDI), and it is simple to install.

Advantages:

• Low cost
• Simple top-up through app
• Flexible plans
• Perfect for light to medium users
• Disadvantages:
• No local telephone number
• Lower data limits (no unlimited plan)
• Not suitable for heavy or business use

3. Ubigi – Suitable for Business Travelers

Ubigi is a worldwide eSIM provider that covers Japan and other nations and is thus a suitable choice for those who travel frequently or are business travelers with the potential to visit several areas. They provide monthly plans and cover high-speed LTE networks in Japan.

Setup is easy with the Ubigi app, and it’s easy to cover several countries under one eSIM profile — which is great if Japan is only a stop on a larger Asia-Pacific journey.

Pros:

• Compatible in multiple nations
• Affordable costs
• Uncluttered user interface
• Excellent network coverage

Cons:

• Not Japan-specific (local number not available)
• Less generous data for the price than Mobal

Final Thoughts

If you’re staying in Japan for more than two weeks, a high-quality eSIM can be a game-changer. It offers convenience, flexibility, and the freedom to travel without worrying about public WiFi or SIM card kiosks. While budget-friendly options like Airalo may work for light users, services like Mobal stand out for serious travelers needing long-term reliability, strong data coverage, and the added benefit of a real Japanese number.

Whether traveling for study, business, or leisurely discovery, selecting the best eSIM is all about improved connectivity and less hassle — allowing you to concentrate on enjoying the best of Japan.