Japan LTE prepaid data plans


The quickest way to pick a provider is to look at amazon.jp ranking of sim cards.  Note that many of the cards come with no minimum contract term and no activation fees (unlike the deals through kakaku that instead offer moneyback (which is too much hustle for me)).  But you might want to look at kakaku‘s ranking since it provides a better summary.

I had good experience with DMM, and Mineo; actually am using both (with my dual sim phone).  DMM’s speed tends to be a bit better; however Mineo lets you share data with others (e.g. my wife).

Note that some people get lower speeds due to the lack of supported frequencies on their phone; for NTT docomo LTE it is 1800 and 2100 Mhz; you can double check frequencies of you phone (nifty site).

If you need to buy a phone and are not in a hurry I recommend AliExpress (shipping could be slow though 21 days).  KiMovil provides one of the best search/comparison UI’s.


I am quite proud of no longer being dependent on evil japanese cell companies.  My total monthly phone bill is now ~$9 (with phone, internet, and some international calling); comparing to $60+.  Below is how I did it.


Major Japanese cell/mobile carriers (SoftBank, Au, NTT) would have you believe that you have no other option but to sign a 2-year contract with them at $40 + / month.  My experience was particularly bad with SoftBank after paying $50 / month and getting 400kbps on my personal phone (contrasting with getting awesome 40 Mbps on my work phone (w/ NTT the lesser evil major mobile company)); and then SoftBank refusing to unlock iPhone after the 2-year contract was up.

Data Plan (LTE)

Kakaku now allows you to compare various sim card plans (select on the left the options that you need; and Chrome does a good job at translating them).

Luckily there are other much better options.  A friend of mine just got one from DMM; and is getting 3MBps speeds; starting from 660 Y / 1Gb / month.  My favorite one being U-mobile (Double Fix) that costs either $7 / month for 1GB; if exceeded automatically becomes $20 / month for 3GB; thereafter unlimited but speed is degraded to 128kbps. (unfortunately Umobile’s speed has deteriorated to kbps). Another option that I like is OCN $16 / month for 2GB (with nice top up cost of $5 / 0.5GB).  You know can also get a prepaid sim at a store such as BIC Camera; which even provides a test sim to ensure that you phone is compatible (thanks to Mike for pointing it out); it also allows you to rollover unused data to the next month.

There are also other descent prepaid providers including bmobile dti iijmio ocn plala rakuten amazon biglobe.

Note that while some providers offer cheap initial packages; their top up costs could be quite high; e.g. bmobile $5 / 100MB; OCN’s offer seems to be one of the most reasonable ones at $5 / 0.5GB.

Most of MVNO sims are on the NTT network; so if your phone is from NTT it should work on these networks (pointed out by Mike).

If money is no object TreMobile provides unlimited prepaid lte plan (unlike softbank or ntt where unlimited ends at 3GB) for $990 / year.
I recently bought another year with  TreMobile (for my work) and their service has become beyond horrible; 2GB limit (previously unlimited); once you are over the limit the speed is supposed to be 200Kbps, but I’ve only gotten 5Kbps (not enough for anything; even email).  Wasn’t able to use their sim card in my phone either; so basically useless; I get a better service from Umobile at 1/10th of a cost.  Called customer service and was unable to either get a refund or to change to a different plan.


Phone Number

You can even get a free 050-xxx (voice) number through SmartTalk; (you can install their app; or if you are a little bit tech savvy you can directly configure SIP on your phone).  Their rates are very cheap ~$0.16/min (Japan and International)
NOTE: These VOIP/SIP phone numbers are not capable of dialing emergency numbers such as 119, etc.; here is a more complete list of providers.

You can also get # usable with SMS for $1.5 (from the data provider).

p.s. Phone-wise I highly recommend getting a nexus phone (had very good experiences with nexus 4 and 5).

p.s. most of the providers actually use NTT’s network; since I think NTT used to be a national carrier; hence has to provide access to its network.


While most carriers claim lte speed 100+ Mbps; not many of them actually reach it.  B-mobile was quite horrible in my experience at around 200 kbps.

This post provides a test run through many of the providers (although some of it for so called “turbo charge” mode).

IIJmio OCN BB.excite Japan Communications Rakuten
Maximum velocity Up 112,500 112,500 112,500 112,500 112,500 7,200
Down 37,500 37,500 37,500 37,500 37,500 5,700
No limit (at night) Down 1,638 5,426 2,994 2,239 4,267 1,498
Up 583 2,032 1,790 2,100 1,467 368
ping 261 74 178 119 74 231
No limit (early morning) Down 12,365 10,318 10,839 6,198 5,453 2,685
Up 2,021 1,396 2,152 1,938 608 390
ping 89 83 77 61 112 353


And other post:

3:00 pm Monday units
1.15 1.36 0.27
9:00 pm Friday units
0.39 0.33 0.13
5:00 cars Saturday morning
2.35 2.07 1.62
11:00 am Saturday units
0.41 0.90 0.23



To make sure that your phone supports bands in Japan; you may want to double check it on: https://www.frequencycheck.com/models






Very comprehensive table of current offerings (may need to filter & sort to see the good plans): http://ma-bank.net/word/92/

VOIP: http://iphone.f-tools.net/Two-SmartPhone/Fusion-IP-Phone-SMART.html


Other refs:




Some of the providers offer VOIP numbers (050, 070); $0 from , $3 from NTT, $5 from Skype Number; am not sure how reliable it is during the emergencies though (although right after the last big earthquake the internet worked much better than the phone lines).

keywords: prepaid data plan 3g 4g lte japan tokyo cheap inexpensive no yearly contract, mvno japan prepaid data sim overview comparison recommendations US Canada EU Europe


About Neil Rubens

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19 Responses to Japan LTE prepaid data plans

  1. Evian says:

    I know this post is a little bit older, but do you mind answering questions about u-mobile?

    Their new website said some time, that customers would be able to make emergency calls, but they changed it again.
    (From “090・080・070”番号を使った通話が可能なので、警察や消防への緊急通報ができ、安定した通話を行うことができます。”

    to “U-mobile 通話プラスは、スマートフォンをすでにお持ちの方向けに、高速データ通信や“090・080・070”番号を使って通話が行える、音声通話機能付きSIMカードをご提供するプランです。”)

    Are these also VoIP-services? And are they, or are they not capable of calling emergency lines like ambulance or police?

    And what are your experiences about the speed u-mobile’s LTE?

    Thank you in advance 🙂

    • Neil Rubens says:

      A friend of mine had umobile several month ago; he got about ~5Mbps.

      As for ability to call emergency numbers; I am not really sure; my uneducated guess is that if you see mentioning of MNP (you might be able to; but one again its just an uneducated guess).

      • Evian says:

        Thank you for your answer. So 5mps would be really slow… But I think I’ll give it a try anyway. Do you know where your friend was located?
        As I will be staying in central Tokyo, I hope for a better connection speed…

        • Neil Rubens says:

          My friend tried UMobile around central Tokyo. Actually being in a populated area might actually result in a worse speed; since most are MVNO operators (using NTT line, and recently sometimes KDDI) and they do speed shaping (e.g. bmobile’s speed was varying greatly for me). Please let me know what speed you end up with.

  2. Amy says:


    I will be going to Japan in September for a one-year exchange. Umobile sounds great with their prices and I’ll be using my own phone. May I know if they are under CDMA or GSM? My telco uses GSM so I have to make sure of that. Also, I don’t know how MNP works, but if I apply for Umobile calls plus 3GB I will be able to make and receive calls, just maybe not to emergency numbers?

    Thank you. I have been really trouble by the phone plans in Japan.

    • Neil Rubens says:

      Most of the phones in Japan are GSM. One thing that you should make sure of is that you phone is not sim-locked.

      MNP is for porting your existing Japanese number between providers; so would probably not be an issue for you.

      Kakaku now allows you to compare various sim card plans (select on the left the options that you need; and Chrome does a good job at translating them).

      UMobile or Mineo are probably a good fit; you can get discounts if you click on them through kakaku.

  3. Evian says:

    Was anyone able to active/register the u-mobile plans via internet with an foreign credit card?
    I purchased a u-mobile package at yodobashi camera (the voice call able one), but whenever I want to complete the registration, I only get an error message. It says they wouldn’t be able to idetify my credit card.
    It’s a normal visa credit card which was widely accepted at Japanese ATMs, Japanese amazon, JLPT registration etc.

    2 other people who also bought the same package at Yodobashi have the same problem, also with European credit cards…
    Maybe u-mobile doesn’t take foreign credit cards? Any other experiences so far?

    • Evian says:

      In addition:
      Could anyone who made a experience with Japanese third party mobile-providers (OCN, IllMio, u-mobile, bigglobe, etc.) post whether or not they accepted a foreign credit card for registration/payment?

      Maybe this could be really useful for us fellow “gaijins” 🙂

      As mentioned before, u-mobile only gives the message of being unable to identify (European) credit cards. No matter how you change the input information of name (katakana, hiragana, alphabet), number etc.

      • Neil Rubens says:

        A friend has used a US-issued credit card and it did work. Are you by chance using Maestro and Visa Electron cards; this might be the problem.

        p.s. I used US-issued cards several times online without any problems.

      • Josh says:

        Hi Evian, did you manage to fix this? I am struggling with the same problem. I have used three different cards and all sorts of combinations of Hirigana and Katakana but no luck!

  4. Ryan says:

    Care to share what you’re using now, and your current experience? My wife and I’s SoftBank contracts are expiring soon and I would love to get away from them.

  5. Derek says:

    please excuse my ignorance, I have just bought my 1st ever mobile ,.. understanding data , data voice plans , sims etc has been an education.
    In Australia , I have a prepaid , 1 year SIM ,[ the mobile number is attributed to the Sim ]…..
    and add to that a month by month , 1Gb+ SMS + voice calls, etc PLAN.

    We visit Japan once or twice a year for a month [ visit inlaws ] & I usually use my iPad with a rental pocket wifi.
    I want to use my new iPhone in 日本 as a phone.
    I get the data bit above but am not clear on how I get a 日本 phone number.
    I assume I need to get a Sim.
    日本 wife with 日本 bank acct for registering stuff.
    please advise.

  6. ishehigh says:

    Hi, I’m going to Japan with my family tomorrow(so I’m in a hurry)
    I’m going for about a week. So I hope if you can tell me if I can buy a sim card in Japan? I’ll only need it to contact my family locally in Japan if one of us ever gets seperated(so I’ll only use it a little)

    I’ve read online that we can rent sim cards or phones in Japan but they’re all extremely expensive!

    Please tell me if you know any affordable sim card that Japanese use

  7. noah s says:

    So where to start.

    Firstly, voice Sim card are basically not available to visitors, so having an overseas card not work is hardly surprising. Buy a prepaid visa or JCB card in the convenience store and use that, but don’t be surprised is they ask for you to upload some ID as proof of residence.

    While they are not the absolute cheapest, I use so-net and OCN voice Sim cards.
    Both are less than 2000 yen per month including data and basic voice. Then you can use 050 plus it phone for most calls to get a cheap per minute rate.

    As for GSM vs. CDMA, this is getting tired. ALL Modern phones are CDMA. The only question is whether they are CDMA2000, or WCDMA. this matters because Japan has never actually supposed GSM at all, so 2G GSM phones will not work in Japan. At any rate, even if your phone is unlocked, you have to worry about frequency support of different phone models and carriers.

    If you are only going to be in Japan for a week and you want an easy to use way to call the other members of your party, you can now get Free phone rentals at the airport. You just pay for the minutes you use.

  8. Adi says:

    I have an enquiry, for example if I purchase the U Mobile data sim for ¥ 2,480 at Amazon, how do I choose which plan that I am going to use and how to pay for it?

  9. Mike says:

    The BIC SIM uses IIJmio company, which piggy-backs off of Docomo network.
    So it’s pretty safe to say that if your global device (phone/tablet) works on those frequencies, then you’re good to go.
    BIC SIM has a TEST Sim, and they’ll test your device to make sure it can work before you go ahead and set up a contract.
    BIC SIM requires a credit card (maybe possible to use International one, but not sure).
    They require ID, and I presume you need to have a Japan address on your ID in order to make the contract.

    There’s no English support as far as I know about BIC SIM service, but you can manage your account by internet.
    You can buy coupons to increase your GB quota if you reach your maximum before the month is up.
    If you reach your maximum quota before your month is up and don’t get any coupon to increase it for that month, you’ll be running at reduced speed (200kbps) until the next cycle. (no extra charges).
    If you don’t use up your total quota during your month, it will roll over to next month (it won’t accumulate month by month).
    i.e. 10GB monthly plan. You use 8 GB, next month you’ll have 12GB
    If you only use 1GB the next month, only 10GB will roll over to next month (will then be 20GB).
    On a 10GB monthly plan, maximum one-time rollover to next month is 20GB, for 5GB then 10GB etc etc.

    All in all it looks promising to go with this service for unlocked devices.

    Also I was told that, if you have a locked Docomo device, and you’re not in a 2 year contract with Docomo, then your device won’t need to be unlocked to use BIC SIM, as the SIM already uses the Docomo network. (IIJmio affiliate company)

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