Bulk SMS in Japan goes either through international routes, which accept alphanumeric IDs and long codes without registration, or through domestic routes, which need sender registration but deliver better; marketing needs opt-in under the Act on Specified Electronic Mail. VoIP in Japan is regulated by MIC, and as of 2026 scam calls from abroad have led to stricter ID checks on 050 IP numbers and free international call blocking for consumers.
Rules last checked: October 2026.
Bulk SMS in Japan: international vs domestic routes
| Route | Sender | Registration |
|---|---|---|
| International gateway | Alphanumeric ID or international long code | None, but some carriers alter the sender (KDDI prefixes international numeric senders with 010) |
| Domestic gateway | Japanese long code or short code, dedicated or shared | Mandatory, a few weeks of provisioning |
For OTP and banking alerts, the domestic route is the safer choice: recipients trust a Japanese number, and international traffic is filtered more heavily because of smishing. Long messages to KDDI (au) with more than five parts may be delayed. See direct SMS routes and SMS route types.
Opt-in and restricted content
The Act on Regulation of Transmission of Specified Electronic Mail applies to advertising SMS as well as email: you need prior opt-in consent, must identify the sender and must offer an opt-out. MIC and the Consumer Affairs Agency enforce it. Routes commonly refuse:
- gambling, adult content, loans and money lending, political and religious content;
- firearms, controlled substances, cannabis and alcohol;
- phone numbers inside the message text, on international routes.
Japanese text is sent in Unicode, so a single SMS holds 70 characters. More in SMS content restrictions.
Japanese mobile networks
The four networks are NTT Docomo, KDDI (au), SoftBank and Rakuten Mobile, plus many MVNOs on their networks. Mobile numbers start with 090, 080 or 070. Test each network separately, as delivery and sender handling differ between them (how to test an SMS route).
VoIP in Japan: regulator and numbering
VoIP is legal in Japan. The Ministry of Internal Affairs and Communications (MIC) regulates telecoms under the Telecommunications Business Act, and providers must register with or notify MIC before offering service. Numbering:
- geographic numbers start with 0 plus an area code (03 Tokyo, 06 Osaka);
- mobile numbers start with 090, 080 or 070;
- 050 numbers are IP phone numbers, used by VoIP services and smartphone apps;
- 0120 and 0800 are freephone.
Rate decks price fixed, mobile and 050 separately. See mobile termination rates.
CLI and anti-fraud measures in Japan
Phone scams in Japan have moved to international calls: Tokyo police data shows international numbers behind about 70% of fraud calls in 2024 and around 80% in the first half of 2025. The response, as of 2026:
- in April 2025 MIC asked telecom carriers to step up measures against phone and impersonation scams;
- consumers can suspend incoming and outgoing international calls on landlines for free through the International Call Blocking Center, and MIC opened a nuisance call consultation center in June 2025;
- since April 2024, the identity checks required for mobile contracts also apply to app-based 050 phone services because of their use in fraud.
For buyers, calls to Japan that present international numbers face more user blocking and lower answer rates, and providers ask for KYC before giving Japanese numbers. Present a CLI you hold and expect checks on traffic type. See KYC for telecom carriers and CLI spoofing rules.
What buyers ask for on Japanese routes
- CLI delivery and which CLI the route accepts (CLI vs non-CLI routes).
- Rates for fixed, mobile and 050, plus ASR and PDD.
- For SMS: domestic vs international route, registration time and OTP latency per network.
Check coverage on the Japan VoIP destination page and the Japan SMS destination page, or read about our VoIP termination and A2P SMS routes. VoIPMatcher sources the route from its carriers and manages it; buyers and sellers never see each other. Request a Japan voice route or request a Japan SMS route.
Frequently asked questions
Can I use an alphanumeric sender ID in Japan?
Yes, on international routes, which accept alphanumeric sender IDs without registration. Domestic routes use Japanese long codes or short codes and require sender registration. Domestic delivery is usually more reliable and trusted by recipients, so many senders use it for OTP and important alerts.
How many characters fit in an SMS to Japan?
Japanese text uses Unicode, so one SMS holds 70 characters, and longer messages are split into parts of 67 characters each. English-only text in GSM-7 holds 160 characters. Long messages to the KDDI (au) network with more than five parts may be delayed, so keep OTP and alerts short.
What is a 050 number in Japan?
A 050 number is a Japanese IP phone number not tied to a location. VoIP providers and smartphone calling apps use them. Because some were used in phone scams, Japan extended identity checks to app-based 050 services, so expect KYC when you request them. Wholesale rates for 050 often differ from fixed and mobile.
Do I need consent to send marketing SMS in Japan?
Yes. The Act on Regulation of Transmission of Specified Electronic Mail covers advertising SMS as well as email. You need prior opt-in consent, must show who the sender is and must include a way to refuse further messages. Keep consent records, since the regulator can request them.
Need a route?
Send the destination, route type and target rate. We reply with what we can deliver.