Length of an SMS
In this article we will discuss SMS rules regarding the length of an SMS. Note that we will differentiate between the length of a single SMS and the length of an SMS message.
Character sets
To determine the maximum length of an SMS or a message, you first need to know which character set you are using, which is usually determined by the use of special characters. For SMS we use GSM-7 and Unicode character sets, which each have a different maximum amount of characters. Please check here to see which character set is applicable for your SMS: Using special characters & non-native languages to send SMS
Length of an SMS/SMS Message
When you know which charset you are using, we can look at the length of your SMS and your message.
An SMS can contain 160 characters when sending with GSM-7, and 70 characters when sending with Unicode. If your SMS contains more than the stated character limit, in most cases we can still send it as one SMS message unless local restrictions dictate otherwise. This is called a concatenated SMS.
An SMS message can have a total of 1377 characters in GSM-7, and 603 characters in Unicode. Note that you are charged per SMS, and not per message.
For example, the below SMS message consists of 264 characters in GSM-7. This means that this message consists of 2 SMS. To send this to the recipient, you will be billed the cost of sending two SMS to the destination country.
How do I know the number of SMS?
Using the table below, you can check the amount of SMS you will be sending based on your character count:
Number of SMS
Maximum GSM characters
Maximum Unicode characters
1
160
70
2
306
134
3
459
201
4
612
268
5
765
335
6
918
402
7
1071
469
8
1224
536
9
1377
603
If you’re sending a message from the Dashboard, there is a counter that indicates the amount of characters and SMS you’ve used in the bottom right-hand corner of the text box where you enter the message.
Restrictions
Not all countries support concatenated SMS and might handle multi-part SMS in different ways. You can check if the country you want to send messages to does or doesn't support concatenated SMS in our country info & restrictions.
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