Last month, number portability came into effect in Japan. Customers can now switch mobile providers and keep their phone numbers. Softbank Mobile (formerly Vodafone Japan) made big news with a new flat-rate plan and a promise always to undercut the other two big providers by 200 yen per month.
Frugal guy that I am, I've been researching the different providers for the best deal. Japanese bloggers have written a lot about the different providers' plans, but there isn't much out there in English. I'm by no means an expert, but I'll share what I've learned.
Softbank's flat-rate plan (Gold Plan) has a basic monthly rate of 2880 yen and advertises free email and free calls to other Softbank subscribers. There are a few catches though (aren't there always).
* There is no monthly call allowance to phones other than Softbank. The first minute of the first call to a fixed line or another mobile phone company is charged in addition to the basic monthly fee.
* Softbank to Softbank calls are not free if calls exceed 200 minutes per month between 9PM and 1AM. That's about six minutes per day during those hours.
* Subscribers to the Gold Plan must sign a two-year contract called "New Super Bonus." This "Bonus" basically means Softbank subsidizes the cost of the phone. A subscriber who doesn't fulfill the whole two years has to pay whatever is left on the price of the phone. (Most phones are tens of thousands of yen.)
This plan is good for people who mostly talk to other Softbank subscribers in the off-peak times and don't mind a two-year commitment.
I spent some time in the Softbank shop the other day and after asking a lot of questions, found that the Orange Plan and Blue Plan are the same as plans offered by Au and Docomo respectively, but 200 yen cheaper. Au has two 3G systems with two price plans so Softbank also has the two price plans even though they only have one 3G system. The Softbank associate recommended the "Orange Plan W" and mysteriously kept his hand over the "Orange Plan X" page of the brochure. Surprise! The "X" plan is less expensive.
I've been a Softbank user since the J-Phone days and have over four years in the system. Rather than swtiching to another company, I'll probably go with the Orange Plan (X) Economy package. I'll wait another month or so and see if Docomo or Au run an enticing campaign and then finally upgrade my antique phone.
In a nutshell, I learned that there isn't much point in changing carriers. Unless your calling patterns fit the profile of the ideal Softbank Gold Plan user, price differences aren't that big. Especially considering the issues of network coverage, and changing email addresses, if you are happy with your current service, just keep it.
If you're interested in comparing, here are Softbank's, Au's, and Docomo's price plans. Be aware that the price of the handsets and each carrier's various discounts can greatly change the final price you pay.
Edit 11/24/2006: If you are interested in changing providers and are having some trouble with the process, please see this post at tsukublog for an excellent English explanation.