Off Topic Need help understanding cell phones in Japan


Cable-Tie Ninja
Original poster
Jul 17, 2017
Looking to buy a new cell phone, but I want to make sure it'll work in Japan when I'm heading there next year. Everything I read says Japan is CDMA only, but shows only LTT and UMTS bands for the two biggest carriers Softbank and NTT.

How do I know what phones will and won't work on their network? Specifically, my wife really likes the razer phone, which is a GSM only phone.

I've also read that the OnePlus 6 works, but it looks to have a very similar frequency support list to the razer phone.


Minimal Tinkerer
May 7, 2018
Looking at the phones on their websites tells me that they support:

  • GSM: Quad-band GSM UMTS: B1/2/3/4/5/8
  • LTE: B1/2/3/4/5/7/8/12/17/19/20/25/26/28/29/30/66
  • TDD LTE: B38/39/40/41 TD-SCDMA: B34/39

OnePlus 6
  • FDD LTE: Band 1/2/3/4/5/7/8/12/17/18/19/20/25/26/28/29/30/32/66/71
  • TDD LTE: Band 34/38/39/40/41
  • TD-SCDMA: Band 34/39
  • UMTS (WCDMA): Band 1/2/4/5/8/9/19
  • CDMA: BC0/BC1
  • GSM: 850/900/1800/1900 MHz

And using the information given from the website (frequencycheck) for Softbank and NTT, both phones are supported by some on the networks the carriers uses.

To make it easier to read:
Green = Supported by both phones
Yellow = Supported by one of the phones
Red = Not supported by any of the phones

  • B1
  • B8
  • B11
LTE (4G)
  • B1
  • B8
  • B9
  • B41

NTT Docomo
  • B1
  • B9 (OnePlus 6)
  • B19 (OnePlus 6)
LTE (4G)
  • B1
  • B9
  • B19 (OnePlus 6)
  • B21
  • B28

So it looks like you won't have a problem with any of the phones, especially if your going with Softbank. Outside of cities in rural areas might be another question tho.
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