Vietnam SMS Brandname: Registration and Template Rules

Every business SMS to Vietnam needs a registered brandname (alphanumeric sender ID) and, on the main operators, pre-approved message templates. As of 2026, unregistered sender IDs are blocked, the brand name must also appear in the message text, and many international routes carry only OTP and transactional traffic.

Rules last checked: October 2026.

The legal framework

Vietnam's anti-spam rules come from Decree 91/2020/ND-CP on fighting spam messages, emails and calls, with Circular 22/2021/TT-BTTTT adding detail. The decree requires advertisers to use registered brandnames (in Vietnamese, "ten dinh danh"), created a national Do Not Call list that users join through the 5656 system, and requires consent for advertising messages. The Ministry of Information and Communications, which supervised these rules, was merged into the Ministry of Science and Technology in 2025, and telecom oversight now sits with that ministry. We did not find a decree that replaces Decree 91/2020 as of 2026; ask your provider whether any new rules apply to your traffic.

Brandname registration

Registration is done by your SMS provider with the operators, using your documents. Expect to provide:

• a business registration certificate (a colour copy) and a signed letter of authorization
• proof that you may use the brand if the brandname differs from the company name (trademark or domain)
• sector licences where relevant: finance and banking content needs a State Bank of Vietnam licence, insurance a Ministry of Finance licence
• the message templates you will send, with variables marked

Brandnames are up to 11 characters, must not be generic (for example "INFO" or "WEB2SMS"), and are case-sensitive: "Brand" and "BRAND" are two separate registrations. Providers quote around five weeks for approval across the major networks, and approvals only happen on Vietnamese working days. Numeric sender IDs are not accepted for A2P. See how sender ID registration works.

Templates, content and the brand name rule

• Templates: MobiFone, Vinaphone and Viettel require the templates to be registered once the brandname is approved. Messages that do not match a template can be rejected.
• Brand in the text: since August 2024 the message body must include a brand or app name that matches the registered sender ID, for example "[ABC] Your verification code is 123456".
• Links and numbers: some providers report that URLs, chat app links and phone numbers in the body are not allowed on their routes. Check before you include any.
• Restricted content: virtual currency, gambling, adult content, loans, political and religious content, alcohol and controlled substances are prohibited or need special licences. Charity and voting content are also refused by several providers.

More on this in our guide to SMS content restrictions.

Promotional traffic and sending hours

Promotional SMS uses a separate brandname registration, which needs extra documents, and several international CPaaS providers do not carry promotional traffic to Vietnam at all. Where it is allowed, marketing messages between 8 PM and 8 AM are prohibited, and each operator adds its own blocked windows (including lunch hours). Consent and the national Do Not Call list apply. Customer care messages that are really periodic promotions are treated as promotional. Read transactional vs promotional SMS.

Mobile networks and encoding

Viettel, Vinaphone (VNPT) and MobiFone serve the vast majority of subscribers, with Viettel the largest. Smaller networks include Vietnamobile, Itel, Wintel and Gmobile. Vietnamese with diacritics needs Unicode, which cuts a message to 70 characters, and some networks do not accept Unicode for certain traffic types. Most senders therefore write Vietnamese without diacritics in plain ASCII, as in the provider OTP examples. Details in GSM-7 vs Unicode encoding.

OTP traffic

OTP is the easiest use case to get approved, but it still needs a registered brandname and template. Include the brand or app name in the text, register the exact OTP template, and be ready to show screenshots of your login to OTP flow, which some operators ask for. Delivery reports are not available on every network, so test before launch with our guide on how to test an SMS route, follow the OTP SMS best practices, and plan a fallback channel.

See our Vietnam SMS destination page and our A2P SMS routes.

Getting a route

Requirements in Vietnam vary by operator and are updated often, so confirm template and brandname rules with the route provider before launch. VoIPMatcher sources the route from its carriers and manages it; buyers and sellers never see each other. Send us your brandname, templates and volumes and request a Vietnam SMS route.

Frequently asked questions