How to sidestep Japan’s unconventional prepaid cellphone law

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Cell Phones Japan’s telecommunication laws prevent those who do not have a valid ID card from procuring any kind of cellphone or telephone that has a telephone number attached to it. For foreigners in Japan, that means either the new Residence Card, or the soon-to-be-obsolete Alien Card will be needed, along with a visa with at least one year’s length of time left on it. Unlike most other places in the world, it isn’t possible to buy a pre-paid phone without this requirement.


For newcomers into Japan who are waiting on their long-term visas or short-termers who will be here under one year, life is really tough. There are a few choices around this perplexing problem though:

A lot of employers will purchase a cellphone on their account and loan it to you. If that isn’t the case, then you can always go the phone rental route. I don’t recommend this due to the exorbitant costs involved.

Which leads me to my recommended course of action: Purchasing an unlocked (SIM-free) smartphone and getting a prepaid SIM card. This is from my own experience about 5 years ago, but it still holds true and today there are even more options in this vein.

“But wait–you said prepaid options ALSO require you to have valid ID and a long-term visa!” True, but read between the lines; I said prepaid PHONE. The law only covers phones, not data devices.

The law hasn’t kept up with technology, and it is extremely easy to communicate using the data-only features of smartphones these days. In fact, most urban Japanese will admit to using apps like, Skype, Google Talk, Facebook, Twitter and email to communicate more than making/taking a voice call. Not to mention you’ll be able to use a number of handy apps like Google Maps, Frommer’s, Japanese translation programs and the like, to make your stay in Japan more manageable.

There are only two companies that are in this space right now: B:mobile and eConnect. Both companies use NTT Docomo, Japan’s biggest cellphone provider for network access. I’ve been able to get coverage literally at the top of Mt. Fuji with them, so if you can’t get a signal with them, then you aren’t in Japan anymore. For the purposes of writing this story, I tested a Motorola Atrix Android smartphone that I bought in the US and has compatible bands for Japan. I then went to the Shinjuku branch of Yodobashi Camera and purchased a B:Mobile Data-Only SIM card.

Once I followed the instructions on how to set the service up on my phone (detailed instructions are on their website as is the actual registration and service setup), I was able to get a clear 3G signal and pull down data in the 2~5 megabit range. This is plenty of bandwidth for using instant messaging and social networks. For me, it was very easy to use Facebook Messenger and Google Talk to keep in touch with people here in Japan, back in the States, and places in between. I didn’t miss having an actual phone number at all. There is also an instant messaging and VoIP app called LINE which is developed here in Japan that almost everyone in Japan uses. The beauty of this app is when you get someone’s regular contact information, LINE does some matching in the background that then can connect you to them without need for needing their username.

I did this experiment for 3 weeks without telling anyone I was doing it. My regular phone was left at home, and the whole time I only received 8 phone calls…3 were from companies calling me for customer service purposes, and the other 5 were friends…who promptly messaged me on Facebook or Google when I didn’t pick up the phone! Not to mention this method is really cheap as well; only Y3400 yen per month and you can cancel anytime. It actually has me thinking about using this method in earnest once my cellphone contract is up.

What you’ll need:

  • Unlocked (SIM-Free) smartphone that supports Japan’s Docomo bands. My personal choice would be Google’s Nexus smartphone. It’s a nice piece of kit, terrific battery life and a LOW price. Plus it’s a true world phone that will work on most networks around the world, including B:Mobile’s. If you’re looking for a different model, check Amazon, Expansys, and others on the net, but make sure it supports 2100Mhz HSPA!
  • B:Mobile SIM card Credit/Debit card to pay for service.
  • Make note of what SNS services your family, friends and colleagues are using BEFORE you do this.
  • If you absolutely need a Japanese phone number, then you can’t beat Skype. They are the only ones that will give you a VoIP phone number within Japan without a hassle as far as set up goes, and the app is available on Android, iOS, and more.
  • If possible, test your setup before leaving your country as well. You want to make sure you’ve downloaded the apps you’ll be using along with setting up any new user accounts for the services you’ll use, if needed.


5 Responses to How to sidestep Japan’s unconventional prepaid cellphone law

  1. Arthur James says:

    If you are able to get Data SIM card then you sign up for 050 plus from OCN it will get you a 050 number with just a credit card. The APP is available on apple and or google. It is ¥350 a month with standard rates for phone calls.

  2. Kirsten says:

    Does this work for iphones?