Getting a phone number in Japan

Ways to get a phone number;

  1. Get a contract phone from one of the major network operators
  2. Get a sim card from one of the Mobile Virtual Network Operators(MVNOs) and use it on the phone you brought from overseas

What are major network operators and MVNOs?

  • Major network operators

The major network operators are the companies which own their own network infrastructure to provide their customers with network services. There are three companies known as major network operators which are au by KDDI, NTT docomo, and softbank. The communication quality and speed are stable and fast compared to the services provided by the MVNOs. The monthly cost is relatively higher compared to the services providedby the MVNOs. If one wants to subscribe for their service, one may be required to purchase a mobile phone device from them as well(i.e. one might not be able to opt to buy a sim card just by itself)*. That's why the services these operators provide are normally referred as "contract phones".
*In case you want to just get a sim card contract from them and use the sim card on the phone you brought from overseas, the service provider must confirm that the phone you brought from overseas conforms to the technical regulations specified in the Radio Law by checking if there's a  "Technical Conformity Mark" on the phone. If they confirm that the phone has the mark, you can opt to make a contract just for a sim card and use it on the phone. If the phone deosn't have the mark, you are required to purchase a phone from them along with a sim card.

  • Mobile Virtual Network Operators(MVNOs)

Mobile Virtual Network Operators are the network operators which rent network infrastructure from the major network operators to provide their customers with their services. The communication quality and speed are not as stable or fast as those of the major network operators. The monthly cost is relatively cheaper compared to the major network operators. One of the advantages of subscribing for their services is that one can opt to buy just a sim card while the major network operators require the subscribers to purchase phones from them when subscribing for their services. If you have brought a phone device with you to Japan, it will be better just to buy a sim card from one of the MVNOs. One can also opt to buy a phone from some of the MVNOs as  some of them sell smart phones for reasonable price.

List of some MVNOs

Major network operators vs MVNOs

  Major network operators MVNOs
Pros
  • Communication quality/speed is high/fast
  • Physical shops available for various support
  • No need to worry about the compatibility of sim card and mobile phone
  • Phone service will be started immediately after making a contract
  • The monthly cost is low
  • Service can be applied online
  • Can have the sim card delivered to your house
  • Can opt to buy just a sim card(i.e. no need to purchase a phone device along with their network service)
Cons
  • Need to visit a physical shop to make a contract
  • The monthly cost is high
  • May be required to purchase a phone along with the network service from the service provider even if you already have a phone(depends on the situation)
  • Communication quality/speed is low/slow
  • Barely find physical shops in Okinawa
  • The sim card might not be compatible with the phone device brought from overseas
  • Need to wait until the sim card is delivered