Each SMS segment sent counts as one reminder. A message may use more than one reminder depending on:
The length of the message
The type of characters used
Any dynamic data inserted into the message
Whether appointment confirmations are enabled
You can see how many reminders a message uses under Settings → Templates, and your usage for the current billing cycle on your Dashboard.
How reminder usage works
Each text message is sent in segments.
One segment = one reminder consumed.
Even if a message appears as a single text on a phone, it may have been sent using multiple segments.
For example:
Message Length | Segments Used | Reminders Consumed |
Short message | 1 | 1 reminder |
Longer message | 2 | 2 reminders |
Very long message | 3+ | 3+ reminders |
How many characters are in a text message?
The answer depends on the character format used in the message.
GSM-7 (standard SMS)
If your message only contains standard characters, the limit is:
160 characters per segment
Unicode (UCS-2)
If your message contains Unicode characters, the limit becomes:
70 characters per segment
Unicode characters include things like:
Emoji
Chinese characters
Some accented characters
Certain symbols
If even one Unicode character is present, the entire message must be sent using Unicode format.
Why you can receive messages longer than 160 characters
Modern phones support SMS concatenation.
This means longer messages are:
Sent in multiple segments
Reassembled on the recipient’s phone
Displayed as one single message
In the past, these would appear as multiple messages arriving quickly one after another.
How we calculate reminder usage
Reminder usage is based on the number of SMS segments required to send your message.
Even if your message appears as a single text message, it may require multiple segments, which means multiple reminders will be consumed.
This mirrors how SMS providers charge for message delivery.
Where to check your reminder usage
For each message template
In the web app, go to Settings → Templates.
Select a template.
Look directly below the reminder text box to see the reminders consumed and/or character count for that message.
For your billing cycle
Your web app Dashboard shows Reminders sent this month, Reminders scheduled, and Reminders remaining for your current billing cycle.
In the Google Calendar add-on
You can also see reminder usage in the Google Calendar add-on by opening an appointment after saving your reminder message.
Note: The add-on calculates the reminder usage after the message is saved, not in real time.
Dynamic data in messages
Your reminder message may include dynamic fields that insert information automatically.
These fields affect the total character count.
Dynamic Field | Character Count |
| 10 characters (DD/MM/YYYY) |
| 7–8 characters (HH:MM pm) |
| 5 characters (HH:MM) |
| Based on your account settings |
| Based on your account settings |
| Based on the event title in your calendar |
| Based on the event location |
| About 40 characters (a short link to the video call), or nothing if the appointment has no video call |
Because calendar titles and addresses vary in length, the exact reminder usage may vary for each appointment.
You can open the appointment in the app to see the exact number of reminders that will be consumed.
URLs and character count
Including a URL or website link in your message can significantly increase the character count.
This may cause your message to require multiple SMS segments, which increases reminder usage.
Appointment confirmations
If Appointment Confirmations are enabled, an additional message is automatically appended to your reminder.
Example appended text:
Confirm or cancel:
https://www.smsreminder.co/confirmation/ZwhFHBRK2wq9sM6KGME_M
This appended message uses 81 characters, which is included in the character limit calculation.
The reminder calculator automatically accounts for this when estimating reminder usage.
How to reduce or optimize reminder usage
If you'd like to reduce the number of reminders consumed, consider the following:
Keep messages short — most messages under 160 characters will use only one reminder.
Send fewer reminders per appointment — many businesses send 1 reminder (24 hours before) or 2 reminders (24 hours + same day). Choose the schedule that works best for your business.
Avoid special characters — emoji and certain accented characters can switch the message to Unicode format, reducing the character limit to 70 characters per segment.
Avoid copying from Word or Excel — copying text from documents can introduce hidden formatting characters that increase the character count. It's best to type the message directly into the editor.
Avoid long URLs — website links can consume many characters and increase the number of segments required.
Keep dynamic fields short — shorter values for
{location}and{from}will reduce the overall message length.Disable Appointment Confirmations — turning off appointment confirmations removes the 81-character confirmation message, reducing reminder usage.
Related
Still stuck?
Start a chat with us using the Messenger in the bottom-right corner and let us know the template name and the message you're sending.