You are entering Vietnam and need to send OTPs, marketing campaigns, and service follow-ups. Using one number for all three? No — Vietnamese carriers strictly separate sender ID types. Use the wrong one and OTP won't arrive, marketing lands in spam, and support gets throttled.
What the three sender IDs actually are
- Brandname: SMS shows your brand name (e.g. 'LOCOM') instead of a phone number. For marketing/notifications — users recognize you instantly.
- Long Code: a sender number in normal phone format that supports direct user replies — built for two-way support.
- Short Code: a 5-6 digit number (e.g. 6070) carriers reserve for OTP/verification/voting — highest delivery rate, fastest.
Four dimensions to set your mix
- Cost: short code billed per message, highest; Brandname per message, slightly lower; long code cheapest but high volume triggers carrier throttling.
- Trust: Brandname shows the brand name, highest trust; short code is OTP-dedicated so users trust it; long code looks like a normal number, worst for marketing.
- Review time: Brandname in Vietnam needs brand registration + review (days to weeks); short code needs carrier approval; long code is instant.
- Replyability: only long code reliably receives replies; short code is mostly send-only; Brandname is mostly send-only.
Our straight recommendation
- OTP / verification → short code (fastest, highest delivery).
- Marketing / brand notifications → Brandname (shows name, high open rate).
- Support / user replies → long code (receives messages, two-way).
Choosing a sender ID isn't about cheapest — it's about reaching the right user in the right scenario. Split the three lines and cost stays controllable.