Why it matters
SMS messages have strict technical limits that can cause longer messages to break into multiple parts or appear incomplete. Knowing how SMS segmentation works helps you avoid unexpected message cut-offs and ensures your content is delivered clearly.
Key Concepts
SMS character limit: Standard SMS supports a maximum of 160 characters per message.
Concatenated messages: When a message exceeds 160 characters, it is split into multiple linked segments.
Encoding overhead: Each additional segment includes metadata that reduces the number of usable characters per segment, increasing the risk of truncation.
Why Messages May Be Cut-Off or Incomplete
SMS messages longer than 160 characters are split into multiple parts. Each part requires header information that decreases the number of characters available. When the total content exceeds what can be supported across segments, the message may:
Be delivered in separate parts
Appear out of order
Arrive partially
Become truncated before completion
Some carriers and devices handle concatenated messages differently, which can lead to inconsistent delivery.
Step-by-Step: Resolve a Cut-Off or Incomplete Message
Verify that the message exceeds 160 characters, which triggers segmentation.
Shorten the message and resend it as a single, concise SMS.
If the issue persists across multiple contacts, the carrier may be responsible for message truncation.
Contact Whippy Support through Help & Feedback so we can escalate the issue with carrier partners.
Tips and Best Practices
Keep messages under 160 characters to avoid segmentation.
Avoid emojis and special characters, which reduce available character space.
For longer content, consider breaking the message into two intentional, shorter messages.
Review your message length before sending high-volume campaigns.
Troubleshooting
Issue | Possible Cause | Fix |
Message appears incomplete | Message exceeded 160 characters | Shorten the message and resend |
Message arrives out of order | Segmented delivery | Send shorter, separate messages |
Multiple recipients report truncation | Carrier handling issue | Contact Whippy Support |
Message with emojis cuts off early | Unicode encoding lowers character limit | Remove emojis and resubmit |