Japan

Overview

There are three major mobile network operators (MNO) in Japan. These are NTT Docomo, Softbank and KDDI (AU). NTT Docomo and KDDI has no prepaid SIM only plans. Softbank has prepaid SIM only plan but the service is mainly for voice. B Mobile and So-net (MVNO of Docomo) has prepaid SIM plans for data though.

Docomo and their MVNO offers 850MHz and 2100MHz W-CDMA service, and 800MHz, 1800MHz and 2100MHz LTE service. Softbank offers 900MHz and 2100MHz W-CDMA service, and 1800MHz and 2100MHz LTE service. There is no GSM service operator in Japan.

B Mobile (MVNO on NTT DoCoMo network)
http://www.bmobile.ne.jp/lineup.html
 * Non-Visitor version


 * Visitors can purchase data-only SIM cards with no restrictions. B Mobile SIM cards can be purchased in major electronics stores, such as Yodobashi, Bic Camera. However the minimum purchase is for 3 months or more in these stores. 1GB card is also available in selected store but note the activation process in the next paragraph.


 * There are 1-month plans and 1GB card, but those cards must be purchased online. The official website is only in Japanese. You can have the card delivered on a specific day within a 3 hours window, to any Japanese address such as a hotel you'll be staying. You can also purchase the same sim in Amazon.co.jp. This website can be changed to English but the product's name is displayed in Japanese. Automated activation is free with a Japanese mobile phone. Otherwise 2500yen activation fee applies and the staffed helpline for manual activation is not open on weekends or holidays.


 * Visitor version
 * http://www.bmobile.ne.jp/english/index.html


 * If you wish to purchase more easily, there is official English website where you can purchase SIM cards. They are the visitor version. The validity is only 14 days and also cost 3980yen which is more than the non-Visitor version. They can be picked up at the major japanese airports with additional 210yen. They are delivered ready to use and no activation required. There are two types of sim:


 * 1) b-mobile visitor sim 1GB prepaid. This product includes 1GB of data up to 14Mbps speed which can be used for every internet services include Skype. This sim is only valid for 14 days.
 * 2) b-mobile visitor sim 14 days prepaid. This product includes up to 300kbps speed data access. VOIP, movie and other streaming contents are strongly restricted.

COMST T-SIM (MVNO on NTT DoCoMo network)
http://www.comst.jp/

COMST T-SIM is a prepaid type of SIM for data communication. No SMS and No voice service available. There are 3 type of plans. All type of plans support tethering function. T-SIM Daily plan package includes a SIM and a prepaid charge card with JPY2k value which is re-chargeable. After activate SIM from your mobile device, provides 31 days data communication unlimited usage. High speed network (LTE) is up to 50MB per day, after that speed goes down to 200kbps until mid-night 0:00am (JST). T-SIM 1GB plan package includes a SIM and a prepaid charge card with JPY2k value which is re-chargeable. After activate SIM from your device, provides up to 1GB data communication under high speed network or up to 30days data communication from your activation. T-SIM 3GB plan package includes a SIM and a prepaid charge card with JPY5k value which is re-chargeable. After activate SIM from your device, provides up to 3GB data communication under high speed network or up to 90days data communication from your activation. Once your prepaid charge card balance goes to 0(zero) value, you may able to re-charge amount at convenience stores such as Lawson, Family-Mart, Mini-Stop, Three-f, Circul-K-Sunkus in Japan. Have to bring your prepaid charge card and cash to stores. After you re-charge to your prepaid charge card correctly, your SIM will be re-activated in shortly.
 * Daily plan: JPY3980 include consumption tax. Exclude shipping fee.
 * 1GB plan: JPY3980 include consumption tax. Exclude shipping fee.
 * 3GB plan: JPY6980 include consumption tax. Exclude shipping fee.
 * How to re-charge your prepaid charge card?

KDDI
No prepaid data plans.

NTT DoCoMo
No prepaid data plans. But a MVNO who does. See B Mobile entry above.

Softbank
Informations about basic prepay plans without data

http://www.softbank.jp/en/mobile/price_plan/prepaid/

Availability

Most convenience stores (Lawson, FamilyMart, 7/11) - http://mb.softbank.jp/en/prepaid_service/purchasing.html

Full info:

http://broadband.mb.softbank.jp/en/download/prepaid_service/3g_prepaid_service_guide.pdf

Prepay data information.

http://www.softbank.jp/en/mobile/service/prepaid/

Note that the above "data communication" refers to using the phone as a dial-up modem; prepaid smartphone data plans are as follows:

Voice pricing is the same as for a non-smartphone, but this must be purchased from a SoftBank store.

Fair usage policy is as follows:

Throttling will be applied from 200MB on the 2-day plan, 700MB on the 7-day plan, and 3GB on the 30-day plan. Additionally, further throttling may be applied at the 1.2GB mark every month at SoftBank's discretion.

Pricing is good for repeat short-term visitors but the 1.2GB/month possible throttling limits the usefulness of the 30-day plan unless using it across two months. The plus side is that for those who need it, only throttling is applied; unlike with B-Mobile's full-speed product or So-Net's SIM you will never be cut off.

So-net (MVNO on NTT DoCoMo network)
http://www.so-net.ne.jp/prepaid/en/index.html

So-net is a Japanese internet service provider operated by So-net Entertainment Corporation owed by the famous Sony Corporation. So-net started to sell prepaid sim card at Narita AIrport(Tokyo) and Kansai Airport(Osaka) from April 2014. From July 15th 2014, So-net starts to sell sim card in the cabin of Peach Aviation's international flights arrives to Kansai Airport.
 * 1) Plan 100M. This product includes 100MB of data up to 150Mbps speed data access for ¥3000. This sim is valid for 30 days.
 * 2) Plan 500M. This product includes 300MB of data up to 150Mbps speed data access for ¥5000. This sim is valid for 60 days.

Both sims can be used for every internet services include VOIP. In Narita Airport, the sim is sold at 1st Terminal B1F Mobile Center and 2nd Terminal B1F Mobile Center. In Kansai Airport, the sim is sold at the a vending machine located at the international arrival gate at 1F.

Refilling is also available on the above page from ¥1620 - 200MB - 30days.

Renting a SIM-card, phone and/or portable WiFi
CDJapan Rental

http://rental.cdjapan.co.jp

no activation required. Data Sim Card
7 days ¥2300 (¥328 / day) 14 days ¥3500 (¥250 / day)

21 days ¥4400 (¥230 / day) 30 days ¥5900 (¥196 / day)

40 days ¥6600 (¥165 / day) 60 days ¥7800 (¥130 / day)

Data only sim card and mobile router/ pocket wifi for rent.

Sally's Rental
http://www.sallysrental.com

Only for using data communications, this is the cheapest rental service.1 week rental cost 3,255 JPY.

Econnect Japan
http://www.econnectjapan.com/

Activation: Card must be activated by using a Japanese mobile phone to a toll-free number, OR a toll call through any other means (such as Skype). English speaking customer service reps are available. Once the call is made, the card is valid for 10 days. They will send a confirmation number by snail mail to you. Once that confirmation number is sent back to them (through e-mail), the card will become fully activated. However, if you are purchasing from econnectjapan, you do not need to activate. They do it for you and you can use it straight away.

Cost for 1 month (free shipping):

"U300" 300kpbs 2980yen (mini or micro SIM)

"Platinum" "プラチナ" UMTS 5280yen (micro SIM only)

APN: comes with instruction booklet. You can clearly see what it is even if you don't read Japanese

Japan Mobile Rental
http://japanmobilerental.com

You can rent a MiFi/pocket WiFi from 1200 yen per day. 3G or 4G packages. Pickup and drop at Narita Airport, Tokyo.

JC Corp
http://www.jcrcorp.com have a number of devices/sims/plans for rental. I went with an unlim data sim on NTT docomo in my unlocked iPhone - worked great even in rural areas. Not cheap, but worth it IMO. Their staff on phone and email all speak perfect english and are very helpful,

Very good overview here: http://www.dannychoo.com/post/en/25485/Japan+Prepaid+SIM.html

Global Advanced Communications
http://www.globaladvancedcomm.com/ for devices/sims/plans for rental. I tried the high speed hotspot and it practically gives you a good strong and very fast data almost everywhere you go--even in smaller towns and on the bullet trains.

Blank-WiFi
http://blank-wifi.com

You can choose 3services 75Mbps/21Mbps/7.2Mbps.And rental fee is from 294/day(shipping fee and extra battery fee are all included).

Sakura Mobile
http://www.sakuramobile.jp

Data only sim card and mobile router/ pocket wifi for rent. Service provided on NTT Docomo Network. Great coverage in rural area. They offer the lowest price for Unlimited LTE SIM cards. Unlimited LTE DATA up to 150Mbps. Sim card works with iphone, ipad, and androids. Sim card is preactivated and ready to use on arrival. They will deliver to hotels or airport post offices.