Special Characters in SMS
Understanding SMS Special Characters
When sending SMS messages, understanding special characters is crucial. SMS encoding determines how messages are processed, and the presence of special characters can impact message length and segmentation. This article outlines which characters are considered special and how they affect your messages.
Non-Special Characters
Non-special characters are those that do not impact SMS encoding beyond the standard GSM character set. These include:
All 26 Latin characters in both uppercase and lowercase (A-Z, a-z).
Numbers 0 through 9.
Certain accented Latin letters, where one version (uppercase or lowercase) is non-special while its counterpart may be special:
- Latin A with Ring Above: Å, å
- Lowercase Latin A with Grave: à
- Lowercase Latin E with Grave: è
- Lowercase Latin I with Grave: ì
- Lowercase Latin O with Grave: ò
- Lowercase Latin U with Grave: ù
- Lowercase Latin E with Acute: é
- Latin O with Stroke: Ø, ø
- Latin A with Diaeresis: Ä, ä
- Latin O with Diaeresis: Ö, ö
- Latin U with Diaeresis: Ü, ü
- Latin N with Tilde: Ñ, ñ
- Uppercase Latin C with Cedilla: Ç
Greek Letters
The following Greek letters are non-special characters:
- Γ (Gamma)
- Δ (Delta)
- Θ (Theta)
- Λ (Lambda)
- Ξ (Xi)
- Π (Pi)
- Σ (Sigma)
- Φ (Phi)
- Ψ (Psi)
- Ω (Omega)
Currency Symbols
Certain currency symbols are also non-special:
- Pound sign (£)
- Dollar sign ($)
- Yen sign (¥)
- Euro sign (€) *
- Generic Currency sign (¤)
Other Non-Special Symbols
Common punctuation and symbols are considered non-special characters:
- @ (At symbol)
- _ (Low line/underscore)
- & (Ampersand)
- * (Asterisk)
- . (Period/full stop)
- , (Comma)
- ! (Exclamation mark)
- ¡ (Inverted exclamation mark)
- ? (Question mark)
- ¿ (Inverted question mark)
- : (Colon)
- ; (Semicolon)
- ' (Apostrophe)
- " (Double quotation mark)
- ( ) (Parentheses)
- < > (Less than, greater than)
- = (Equal sign)
- + (Plus sign)
- - (Hyphen/minus sign)
- % (Percent sign)
- \# (Number sign/Hashtag)
- § (Section sign)
- / (Forward slash)
- \ (Backslash)*
- { } (Curly brackets)*
- | (Vertical bar)*
- ~ (Tilde)*
- ^ (Caret/circumflex)*
*Characters marked with an asterisk (*) count as two characters in an SMS message but are not considered special characters.
Special Characters
Special characters are any other characters that are not listed in the tables above. These include:
- Additional accented Latin characters: À, á, â, ç, ê, É, È, Ì, î, í, Ò, ô, ó, Ù, ú
- Emojis – All emojis count as special characters.
- Unicode Characters – Any Unicode character is considered special, even if it visually resembles a non-special character.
For example, consider double quotation marks:
- Non-special character: "
- Special characters: «, “, ‟, ❝, 〝
Why Special Characters Matter in SMS
SMS messages are typically encoded using the GSM 7-bit standard, which allows up to 160 characters per message. However, when a special character is included, the message may be encoded in UTF-16, reducing the character limit to 70 per message. This can lead to message splitting and additional costs.
To optimize SMS length and avoid unnecessary encoding changes, it's recommended to minimize the use of special characters unless absolutely necessary.
For further assistance with SMS encoding or troubleshooting message length issues, please contact our support team.