You send OTP and promos on the same route. On a big promo day users say 'the OTP took two minutes, I gave up signing up'. The cause usually isn't the network — it's that the route got dragged down by marketing volume, its reputation score dropped, and OTP priority was throttled.
Carriers score reputation per route type
- Each route (Sender ID/line) has its own reputation score that auto-adjusts speed and delivery.
- Heavy marketing, high opt-outs, spam reports → route score drops.
- When the route drops, OTP sharing it also slows and falls into a low-priority queue.
The cost of delay
- A 30-second OTP delay can lift signup abandonment 10-20% at the verification step.
- One marketing 'drag' can slow OTP for the whole following week (until the score recovers).
- Separate routes: OTP on its own line keeps speed and delivery safe from marketing.
How to split
- OTP/service → short code or a dedicated line with speed SLA.
- Marketing → its own Brandname, time-boxed, with opt-out.
- Watch each route's score weekly; if the marketing route drops, pause and recover it.
Splitting routes costs little but saves a whole batch of signups. OTP is revenue, marketing is noise — don't pour both through one spout.
FAQ
What is cross-border SMS and how does it differ from domestic SMS?
Cross-border SMS is sent via foreign carriers (Vietnam, Thailand, Indonesia…) to users worldwide; it differs from domestic SMS in routes, Sender ID, and per-country compliance.
Why is my SMS template rejected and how to fix it?
Usually sensitive words, wrong format, or unregistered Sender ID. Fix: use neutral wording, follow each country's template rules, register the brandname in advance.
Should I choose Brandname, OTP, or P2P SMS?
Brandname for branded marketing/notifications; OTP for verification codes; P2P for 1-to-1 chat. Choose by use case and delivery rate.
How are delivery rate (DLR) and pricing calculated?
Billed on DLR-confirmed successful sends; failed submissions are free. Look at actual delivery rate, not just submit volume.