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9 Best Prepaid SIM Cards in Japan: Buying Guide

When you think of Japan, you are probably thinking of all the flashy billboards in Tokyo, the high-speed train called Shinkansen, or the lovely Japanese food (my partner REALLY loves Japanese snacks, which is tasty, I can tell you!). You probably have heard or seen that Japanese people are polite, clean, and just lovely to interact with – a trip to Japan should be on everyone’s travel list, I believe.

What we are more interested in are the smartphone connectivity options we have when visiting Japan. Roaming with your provider can be expensive because roaming on its own is overpriced. This is why a lot of travelers want to buy a local SIM card when visiting a destination – in this case, Japan. Can you actually buy a Japanese SIM? Some countries put restrictions on who can buy SIM cards. Let’s see what we can do in Japan.

Telecom Providers in Japan

Japan has three networks: NTT DoCoMo, SoftBank, and au. A license to a fourth provider was given a few years ago to Rakuten Mobile, which is bound to be launched in 2020. I am interested to see what they will be offering, especially for travelers like us.

What SIM card should you buy when visiting Japan? If you want to buy a SIM card in Japan, I would recommend getting one from Mobal because they have a wide variety of cards and plans, meaning that you will find one that fits your needs. The Japan SIM Card and one from B-Mobile would be good options too, although B-Mobile is expensive.

It is important to know that there is no 2G network in Japan because it was shut down a few years ago. If you have a modern smartphone, you should not have to worry because it will be able to use the Japanese 3G and 4G/LTE networks. If you have an older phone that cannot handle those speeds, you may want to get a traveler’s phone (but in that case, you probably are not interested in data anyway).

In Japan, you must have gone through the alien registration process to buy a voice-enabled SIM card because, by law, only those who have shown identification and have a residential address in Japan can buy and use a voice-enabled SIM card. Unfortunately, ho(s)tel addresses are not accepted for this purpose.

If you have a temporary resident visa, like a student visa, then you can register yourself. If you are from a visa-free country, then voice-enabled SIMs are not available to you. Unfortunately, I am not sure whether people on an actual tourist visa can register themselves. Most likely not, as I believe tourist visas are not given for more than 90 days, but I could be wrong.

If calling or getting called is important to you, I would recommend using a VoIP app like Facebook Messenger, Whatsapp, of Skype, as the law does not prohibit foreigners from calling from such apps.

Now, let's see what type of SIM cards we can buy.

Tip: Looking for cheap flights? Book with AirWander and add stopovers! Not in a hurry yet? Set up flight alerts with Airfarewatchdog and get notified when ticket prices for your preferred route(s) drop!


Mobal Logo

Mobal offers several different plans – those tailored for long-term travelers or short-term travelers. With the Mobal SIM long-term plan (more than 90 days), you will have access to unlimited data, free incoming calls and texts, a Japanese phone number, and customer support in English. All of this is offered with no contract, so you are free to cancel anytime – perfect for even the most spontaneous of travelers!

Travelers with plans to bounce around countries or just stay for a short time can opt for the short-term plan, which is offered at 16, 30, 31, 60, and 90 days. Depending on the length of your SIM card service, prices may vary and options for unlimited data on talk and text being to open up.

Mobal also offers many different sizes of SIM cards to fit all different kinds of basic- and smartphones.

Japan SIM Card

Although it is not the most distinct name, the Japan SIM Card is right up there with Mobal in terms of abundance of data and flexibility of short-term service. The service ranges from 5 to 21 days and offers unlimited data with each plan.

You can have this SIM card delivered to you anywhere in the world, and, when finally in Japan, you will have nationwide coverage from Japan’s DoCoMo network at 4G LTE. The only catch with this SIM is that your device must be unlocked for it to function in full capacity – so do not expect to get notifications while your phone is locked in your pocket or overnight when charging.

This SIM is also offered in multiple sizes: nano, micro, and standard. A significant disadvantage of this SIM card is that it does not offer voice or SMS – rather, it exclusively offers data. Note, too, that the use of more than 3GB of data per day will result in reduced data speeds for 24-48 hours.


B-Mobile SIM poster

B-Mobile offers SIM cards for periods of either 10 or 21 days, with 5 or 7 GB of data at 4G/LTE speed (or 3G when 4G/LTE is not available). If you wish to have your SIM card before you arrive in Japan, you have the option to purchase your SIM card ahead of time online through stores like AEON, Yodobashi Camera, and BIC Camera. There is an airport pickup option as well.

There are limitations to B-Mobile, though, as your visitor SIM can only be used when your device is unlocked and is only compatible with LTE devices, and devices that are safe to use in Japan.

Find out if your device is safe to use on the Docomo network website.

Smash Mobile

SmashMobile Logo

Smash Mobile is a network running on the NTT DoCoMo network. You can buy a Smash Mobile SIM card on their website (they sometimes have promotions, which will make the SIM cards a bit cheaper, like during Christmas).

Smash Mobile offers the following plans, which are all excluding 10% tax. For reference, 1000 JPY is 9.20 USD:

  • 2000 JPY: 1 GB valid for 7 days
  • 2800 JPY: 3 GB valid for 15 days
  • 4000 JPY: 6 GB valid for 30 days
  • 5500 JPY: Unlimited data valid for 31 days
  • 10000 JPY: Unlimited data valid for 60 days
  • 14000 JPY: Unlimited data valid for 90 days

Ninja SIM by Biglobe

Biglobe's Ninja SIM logo

Biglobe offers the Ninja SIM that runs on the NTT DoCoMo network. You can buy the SIM card on their website or in various stores. For 5292 JPY or 8316 JPY (that includes tax), you can get 5 GB or 7 GB of data, respectively.

NTT Communications, U>mobile, and MAYASystem

NTT Communications, U>mobile, and MAYASystem all offer SIM cards that come with unlimited data. After using a set allowance, which between 200 and 220 MB per day, the speed gets reduced to 200 kbps, which is close to 2G speeds.

Other Ways to Stay Connected When Traveling in Japan

Besides getting a Japanese SIM card, there are different ways of staying connected when exploring Japan, such as using an international SIM card, roaming with your provider, using pocket WIFI, or WIFI networks.

International SIM Cards

You can consider purchasing an international SIM card. International SIM cards are SIM cards that can be used internationally without the roaming charges.

There are many international SIM cards out there, such as OneSimCard, SimOptions, Surfroam, Simcorner, and BNESIM. These SIM cards with the same as roaming with your provider, but the charges are often way less than actually roaming because they have been set up for international travel.

International SIM cards give you the same convenience as roaming with your provider. As in, not having to get numerous SIM cards, you will not use again, and being reachable on one number instead of multiple. In most cases, you can use your international SIM when back home, but their rates will be high compared to using your carrier.

Do note that using an international SIM card is often more expensive than using a local SIM card but cheaper than roaming with your provider. International SIM cards are appealing for those who travel frequently and cannot be bothered with the hassle of purchasing a SIM card each time they arrive at a new destination. Additionally, constantly having to switch SIM cards and using different phone numbers may discourage seasoned travelers from buying local SIM cards.

If you are visiting only one destination for a short period, get a local SIM card (or roam with your provider if they have attractive roaming rates or plans). If you travel often and want to be able to be contacted on one phone number when visiting multiple destinations, international SIM cards could be attractive. Check out my international SIM card comparison article, where I analyzed the top 10 leading international SIM cards out there.

Roaming with Your Provider

Roaming is a term used in wireless telecommunication that indicates a mobile device is outside the range of its home network and has connected to a different, available cell network. If you use your phone in Japan without changing SIM cards, you would be roaming in Japan.

You have probably read numerous horror stories of travelers who went abroad for a while and came back home to a phone bill in the thousands because they were roaming. An example of such a story is this individual who received a bill of £8,348.41 for data roaming for 40 minutes. I also found the reason why roaming is so expensive.

No idea how roaming works? I made this comprehensive guide about what roaming is and how it works. It is worth the read – promised!

Roaming can be convenient because you do not have to wait in line to get a local SIM card, go through the whole SIM card registration process, and can easily be reached when friends and family who are in your home country want to call or text you.

However, this convenience comes at a cost – a high cost if you do not watch out. But this does not always have to be the case.

Some carriers allow you to roam for free in select countries, such as Sprint (American provider). They have a program called Sprint Global Roam, which allows its customers to roam in 205 destinations, including Japan, for free at reduced speeds.

Other carriers allow you to use your plan's allowance if you pay a fixed daily fee. For example, Koodo, a Canadian provider, allows you to use your plan's allowance with their program called Koodo Easy Roam International for $12 a day, which can be used in Japan as well. This means that if you get 10 GB a month, you can use those 10 GB in Japan as well.

However, you should take caution with such plans. They are convenient and inexpensive when done for a few days, but not when going abroad for a week or more. I often argue that one can use these plans if you are staying abroad for a maximum of three days. If longer, than you are better off with a local SIM card, which will give you more bang for your buck. Check out my articles to see if your provider offers roaming bundles.

Finally, you can roam on Pay As You Go roaming rates. With standard roaming rates, you get charged per action on the go. In other words, you get charged per minute, SMS, or KB/MB. Often, Pay As You Go roaming rates are insanely high (which leads to those stories where people got charged into the thousands), and should be avoided in most cases. However, some providers do have reasonable standard roaming rates, especially to neighboring countries.

In general, I would discourage you from roaming on Pay As You Go roaming rates when visiting Japan, but it is still an option to explore. If you want to see what your carrier would charge you, check out my roaming with your provider articles with my analysis and verdicts.

Pocket WIFI

If you do not want to get a local SIM card or an international SIM card and do not feel like roaming either, then you can get pocket WIFI. A portable hotspot is a device that acts as your personal router that you can take with you. This hotspot connects to the cellular networks of your destination – just like your phone would do but without the roaming costs.

There are many portable hotspots out there. Two reputable pocket WIFI companies I know are Skyroam (use coupon code PHONETRAVELWIZ) and Vision Global Wireless (which is a Japanese company). WIFI access with Skyroam starts at $8 a day. Using a Vision Global device starts at $2 a day. Both services cover more than 130 destinations around the world.

A pocket WIFI device is ideal for those who are traveling with families or multiple individuals. This way, everyone can connect to the device and enjoy the WIFI network on the go. Some companies will charge you per GB while others will give you unlimited data. Be aware of the data restrictions of your device so that you will not receive a high bill after your travels.

Using Free WIFI Connections

If you do not want to pay anything extra for staying connected while in Japan, then you can choose to connect to WIFI networks instead of cellular networks.

Although using WIFI hotspots may save you money, it may not be convenient as using a SIM card. First, you would have to find WIFI hotspots. When I was in Tokyo, most cities and suburbs had free public WIFI in town. Sometimes, they worked. Sometimes, they did not (or they were extremely slow). The same counts for hotspots on the trains. If I recall correctly, you only had to accept their terms to use WIFI, but I am not too sure about that.

Additionally, public WIFI hotspots are unsecure. I would recommend using a Virtual Private Network (VPN) if you connect to an unfamiliar network. The VPN will encrypt your data and will keep your data private. I use NordVPN, and you can get up to 70% off when you get a NordVPN subscription. Get your NordVPN subscription today!

The Best Way to Stay Connected When Traveling in Japan

Getting a SIM card from Mobal would do you well when considering a Japanese SIM card. Be sure to explore the roaming options your provider offers you, as they may offer free or cheap roaming bundles.

You could also consider getting an international SIM card or using a portable hotspot. International SIM cards are attractive for those visiting multiple destinations at once or within a year. Portable hotspots will be useful when traveling with multiple people so that not each individual has to get a SIM card but can use the hotspot.

Visiting other countries in East Asia? Check out my East Asian SIM card buying guide, covering other East Asia countries, such as China, Hong Kong, Macau, Mongolia, South Korea, and Taiwan. Going to other places around the world? Then you should also check out my sim card buying guides for other destinations around the world.

What is next?

Looking for the best companies and gadgets to enhance your travel experience? Check out my resource page for the best companies to use when you travel! Save money on plane tickets, bus rides, cruises, and accommodation. Besides that, I also list services and items I use to make my life easier – and I believe they will help you too!

Book Your Flight for Japan

It is time to book your flight. Find cheap flights with AirWander so that you can add free or cheap stopovers in destinations you have not considered yet before going to Japan. If you are not ready to take off yet, set up flight alerts with Airfarewatchdog, and they will notify you once ticket prices to Japan drop.

Book Your Accommodation for Japan

I am a huge fan of Airbnb because it allows me to live with a local or get a local place for myself. Staying in someone’s house or apartment feels much different than being in a ho(s)tel, especially in Japan. At least, that is how I see it. Moreover, Airbnb can often be much cheaper than staying in a Japanese hotel.

Get Your Travel Insurance for Japan

You will regret not having travel insurance once you actually need it and “forgot” to get it. Nowadays, travel insurance is cheap and comprehensive unlike back in the days. World Nomads is by far the best travel insurance for adventurous travelers like yourself. You can even get insured WHILE already traveling in Japan, which is not something many insurance companies allow you to do.

Get a Travel Debit Card

Travel Cheques are outdated. Paying with your credit card or debit card can be expensive because of all the exchange commissions banks charge you. TransferWise allows you to convert your main currency to Japanese Yen for a small fee (up to 8 times less than with your bank!) Getting a Transferwise Borderless account is FREE, so you will get an instant return on your investment.

Enjoy your trip!