Character limits are important to understand as the number of characters in your SMS will affect the cost per message sent. Larger messages are split into multiple parts (units) and pricing is based on those units.
The maximum amount of characters that you can use before your message goes from one SMS using one unit, to one SMS becoming multi-unit and requiring two or more units is:
- Messages containing only "standard" (GSM) characters: 160 characters
After 160 characters your message will become "multi-unit" with a limit of 153 characters per unit. - Messages containing "special" (Unicode) characters: 70 characters
After 70 characters your message will become "multi-unit" with a limit of 67 characters per unit.
Note: These limits will apply to any message containing special characters, even if there are standard characters present as well.
Multi-unit message breakdowns
| No. of Units | Standard Characters | Unicode Characters |
| 1 | 1-160 | 1-70 |
| 2 | 161-306 | 71-134 |
| 3 | 307-459 | 135-201 |
| 4 | 460-612 | 202-268 |
| 5 | 613-765 | 269-335 |
| 6 | 766-918 | 336-402 |
| 7 | 919-1071 | 403-469 |
| 8 | 1072-1224 | 470-536 |
When a message is split into multiple units, some characters get used up by invisible headers and footers, which are used to identify which part of the message is being sent.
Smart Encoding
Our Smart Encoding feature identifies common accidental Unicode characters and replaces them with their equivalent standard GSM character, ensuring the message goes out as GSM and does not inadvertently trigger a 70-character limit on the whole message. Accidental Unicode characters can occur if you copy and paste content from an external source that might contain Unicode characters without it being obvious. e.g. if you've copied across any paragraph formatting like "tab" or "whitespace" characters.
A full table of replacements can be obtained by contacting our support team.
This feature is automatically enabled for your account, and can be toggled on/off at 'SMS Messaging > Settings > Smart encoding'.
Emojis
You can send emojis provided the recipient network supports it (if not supported they will be stripped out). Using an emoji changes the encoding of the message to Unicode - emojis are counted as 2 Unicode characters each.
If you have questions regarding SMS character limits or any other part of our service, please reach out to our friendly award-winning support team for assistance.