Understanding SMS Character Limits

Introduction

SMS, as a communication medium, has specific character restrictions. Knowing these limits is essential when crafting messages to ensure they're received as intended.

Breaking Down SMS Length

A standard SMS is confined to a set number of characters:

- Standard SMS: 160 characters.
- If a message doesn't exceed this limit, it's considered a single SMS.

- Extended SMS: More than 160 characters.
- Messages surpassing this limit are split and sent as multiple SMS. However, due to the need for 7 hidden characters to concatenate the parts, the effective length of each subsequent SMS reduces. Thus:
- Up to 160 characters: 1 SMS
- 161 to 306 characters: 2 SMS
- 307 to 459 characters: 3 SMS
- 460 to 612 characters: 4 SMS
- 613 to 765 characters: 5 SMS
- More than 765 characters: The message will be truncated.

Important Note

The inherent character restrictions of SMS are not platform-specific but are due to telecommunication network standards. When crafting messages, always be mindful of these limitations to ensure clarity and efficiency.

Recommended SMS Length

When crafting personalized SMS messages, it is advisable to limit the character count to 150. This ensures that after adding variables, such as people's names, the overall SMS size is still less than 160 characters.

Example:

Suppose you want to send a message with a variable for the first name. A name can vary in length, so designing the template accordingly is crucial:

- Template: "Hello, {first-name}! Welcome to our service. Reply YES to confirm."
- With a Short Name (e.g., Sam): "Hello, Sam! Welcome to our service. Reply YES to confirm." (68 characters)
- With a Long Name (e.g., Jonathan): "Hello, Jonathan! Welcome to our service. Reply YES to confirm." (73 characters)
By keeping the core message under 150 characters, you provide room for variability in the name length while ensuring that the final message remains within the single SMS limit.

Conclusion

When drafting SMS messages, being aware of character constraints helps optimize the communication process. Longer messages will be split, potentially increasing costs and altering message flow, so understanding these parameters is crucial, including accommodating for variables like names.

Updated on: 23/08/2023