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Understanding SMS Character Count & Charges (Tallbob)

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Summary

Learn how Tallbob calculates SMS message length and units, especially when using Unicode characters such as long dashes (–), curly quotes (“ ”), or apostrophes (’).
This guide explains why SMS charges may differ from what you previously experienced with ClickSend.

This article covers:

How Tallbob Calculates SMS Length

Tallbob determines the number of SMS units based on the type of characters used in the message.

There are two types of message encoding:

1. Plain Text (GSM-7 Encoding)

These are standard ASCII characters such as:

  • A–Z / a–z

  • Numbers 0–9

  • Basic punctuation: . , ! ? : ; ( ) ' "

Message length limits using GSM-7:

  • 1 unit = up to 160 characters

  • Up to 10 units supported

  • Maximum total characters = 1,530

2. Unicode Messages (UCS-2 Encoding)

If your message contains any special characters, it automatically becomes a Unicode message.

Unicode characters include:

  • Long dashes: –

  • Curly quotes: “ ”

  • Curly apostrophes: ’

  • Emojis

  • Accented characters (é, ñ, ü, etc.)

Message length limits using Unicode:

  • 1 unit = up to 70 characters

  • Up to 10 units supported

  • Maximum total characters = 670

Important: A single Unicode character will convert your entire SMS into Unicode format.

Why Your Report May Show Different Message Counts

Recently, we migrated to Tallbob. SMS units are calculated differently.
Messages containing any Unicode characters now correctly count as 70-characters, not 160.

What this means:

  • SMS credit usage is correct

  • Billing is correct

  • The rate per SMS in settings is correct

  • Your SMS base rate applies to 1 unit

Plain Text vs Unicode Character Limits

Message Type Encoding Characters per Unit Max Units Maximum Characters
Plain Text GSM-7 160 10 1,530
Unicode UCS-2 70 10 670
HYPHEN EN DASH EM DASH
dash alt/option + dash alt/option + shift + dash
This is a hyphen-in-action. En dashes replace the to in 9-5. Em dashes break up sentences—like that.

Examples

Example 1 – Plain Text (160-char units)

Your inspection is booked for Saturday at 2:00pm. Please reply YES to confirm.

  • No special characters

  • 1 unit used

Example 2 – Unicode (70-char units)

Your inspection is booked for Saturday – please arrive 5 minutes early.

Contains a long dash (–) → Unicode

  • 77 characters

  • 2 units used

Example 3 – Curly Quotes

Your application for “21 Smith Street” has been received.

Contains curly quotes (“ ”) → Unicode

  • 59 characters

  • 1 unit used

Example 4 – Mixed Message

Great news——your offer has been accepted!

Contains an em dash (—) → Unicode

  • 45 characters

  • 1 unit used

Tips to Reduce SMS Cost

  • Avoid using curly quotes: use "straight quotes" instead 

  • Replace long dashes (–) or em dashes (—) with standard hyphens: -

  • Avoid emojis unless necessary

  • Avoid copying/pasting text from Word, Outlook, or websites (these often include hidden Unicode characters)

    • The SMS modal when sending a standard SMS will notify you if you have added a Unicode character.

If you need help identifying problematic characters or reviewing your SMS templates, feel free to contact the Support Team.

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