International messaging
CSMS
Concatenated SMS for long-form text messages with ASCII and Unicode support.
Service overview
When a message exceeds the standard SMS limit, SureM can automatically convert it into CSMS so longer notices, policy messages, and multilingual communication can still be delivered by SMS.
Core specifications
ASCII limit
Up to 612 chars
Unicode limit
Up to 268 chars
Charging model
Based on concatenated segment length
Format
Concatenated SMS
Length matrix
| Categorization | ASCII | Unicode |
|---|---|---|
| 1 concat | 0 ~ 160 | 0 ~ 70 |
| 2 concat | 161 ~ 306 | 71 ~ 134 |
| 3 concat | 307 ~ 459 | 135 ~ 201 |
| 4 concat | 460 ~ 612 | 202 ~ 268 |
Operational note
Messages longer than five concatenated SMS segments face higher delivery risk, so long notices are better shortened or split for more reliable delivery.
Where long-form SMS fits
Detailed notices
Use CSMS for service changes, customs delays, policy updates, and other messages that do not fit in short SMS.
Longer international text
International LMS-style delivery is suited to content that needs 2 to 3 times more text than short SMS.
Low-friction rollout
Long-form SMS keeps the same basic messaging workflow while extending usable message length for operational teams.
Message example
{
"type": "CSMS",
"message": "Your shipment is delayed due to customs clearance. We will notify you again when it is released."
}Common use cases
- ›Detailed service updates
- ›Multilingual notifications
- ›Long-form reminders
- ›Policy notices