Reason 1 - Sending long SMS
An SMS comprises of segments and each segment is 160 characters long. So if you are sending a lengthy SMS, it will consume multiple segments and thereby drive up your cost.
Please note that while 160 characters form a segment, even using 161 characters counts as 2 segments.
Character lengths of segments also vary by country & region, which might be another reason for your high SMS cost.
Reason 2 - Having hidden characters in your SMS text
Many customers copy/paste the SMS text body while designing automation. When you copy/paste text from a text editor software like MS Word or Google Docs, sometimes hidden characters get appended in the string. These hidden characters can not be seen by the user but they are present in the text.
Example
In this example, a simple phrase Hey there was copied from a webpage. Usually, it should be just 1 segment. But actually, it contains many hidden characters (empty characters) making this as large as 4 segments.
You can use https://twiliodeved.github.io/message-segment-calculator/ to check the actual number of segments & character length of your SMS text.
While pasting the contents of an SMS to the Aesthetix CRM text editor, it is recommended to use the paste as plain text option instead of simple paste
Reason 3 - Using Emojis
This is the most common reason for unexpected high costs while sending SMS automations.
Example
Some emojis used increased the number of segments from 1 to 4.
Using emojis is a great way to make your automation exciting but being aware of the costs involved will help you make an informed decision about their frequency of usage.
Reason 4 - Using a picture attachment
Both SMS and MMS carrier fees will apply which could drive up the cost of each SMS. When you send a picture message with text, you get charged $0.02 for the picture + the usual SMS cost depending upon the length of the text.
For example,
If the following text portion of the Picture SMS is 2 segments -
"Hey Eric, this is Kate from Aesthetix CRM, just wanted to let you know that this upcoming Monday, we have a new update for your practice, REGISTER HERE: aesthetixcrm.com/ or text MOREINFO for more info!"
We will charge $0.0097 x 2 = $0.0194 for the text portion.
If there's an image attached to this message, it will charge at $0.02 / message
So the total cost per message is $0.02 + $0.0194 = $0.0394
Further, there might be some additional charges incurred:
MMS-MESSAGES-CARRIERFEES
PHONENUMBERS
SMS-MESSAGES-CARRIERFEES
We are not in control of carrier fees. This was put in place as part of A2P-10DLC compliance.