> For the complete documentation index, see [llms.txt](https://docs.mercuri.cx/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.mercuri.cx/communication-channels/sms-integration/sms-length.md).

# SMS Length

### 1. How Many Characters Can You Send in One SMS?

* **Standard Messages (GSM-7 Encoding):** Up to **160 characters** per message.
* **Messages with Special Characters like emoji and Chinese characters (UCS-2 Encoding):** Up to **70 characters** per message.

### 2. What Happens If Your Message is Longer?

If your message is longer than the limit:

* **Standard SMS (GSM-7):** Messages are split into **chunks of 153 characters** each and sent separately.
* **Messages with Special Characters (UCS-2):** Messages are split into **chunks of 67 characters** each.

For example:

* A **161-character message** will be split into **two messages** (153 + 8 characters).
* A **71-character message with emojis** will be split into **two messages** (67 + 4 characters).

### 3. Why Do Special Characters Reduce the Limit?

Special characters (like emojis, Chinese script, or fancy quotation marks) use a different encoding system, which reduces the number of characters allowed in one message.

### 4. How to Avoid Extra SMS Costs

* **Keep Messages Short:** Try to stay within **160 characters** for regular text.
* **Avoid Special Characters:** Emojis and special symbols can reduce your character limit.
* **Check Before You Send:** Use Mercuri’s built-in SMS counter to see how many messages will be sent.

***

#### Example of SMS Length & Cost

| Message Type                         | Characters      | Sent As       |
| ------------------------------------ | --------------- | ------------- |
| Hello! Your order is confirmed.      | 30              | 1 SMS         |
| Your order #12345 is 🚀 on its way!  | 40 (emoji used) | 1 SMS (UCS-2) |
| Long message with 161+ characters... | 161             | 2 SMS         |

### Final Tips

* Stick to simple text when possible.
* Use abbreviations smartly but keep messages clear.
* Always preview your message to avoid surprises.


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