Alphanumeric Sender IDs are supported. Numeric Sender IDs will be changed to randomized numeric Sender IDs or "SMS" as a generic Sender ID to ensure delivery.
Sender ID with operators name are restricted: KDDI, Softbank, NTT, Rakuten Mobile. Any Sender ID starts with UQ (including Uq, uQ, and uq) are restricted towards KDDI.
Gambling related content are not supported towards all Japan networks. Messages classified as illegal by the local networks are either discarded completely or the part of the illegal content will be removed.
Preventive Measures Against Phishing SMS
There are preventive measures by Japan networks against phishing SMS that may affect delivery of messages with URL link.
- NTT Docomo network
- Messages with URL link will not be delivered by the network if it meets their undisclosed rejection criteria.
- Softbank network
- Subscribers can change the "Junk SMS filter" feature setting to "Strong" (default setting is "Standard") via Softbank's app/portal, which may affect delivery of messages with shortened URL.
- Subscribers also have the option to activate the "Reject SMS with URL link" feature via the app/portal.
Japanese characters unicode SMS are supported, and for other languages it depends on the handsets.
Concatenated messages are supported to all networks.
The maximum length/char for unicode messages is 670 full-width characters for Docomo, KDDI, Softbank, and 660 full-width characters for Rakuten.
Other Features or Restrictions
Network level delivery receipts are supported.
For more information, see the following articles: