SMS Billing

The cost of sending an SMS depends on its length, which is determined by the type of characters used in the content. The system automatically selects the appropriate encoding (GSM-7 or Unicode), which directly affects the character limit in a single message.

The following rules comply with global GSM standards and apply to all shipments (both from the web app and via API).

Standard Message (GSM-7 Encoding)

If your message consists exclusively of characters from the basic Latin alphabet, digits, and basic symbols, it is encoded in the cost-effective GSM-7 standard.

• Single SMS: up to 160 characters.

• Concatenated messages: Each subsequent segment (SMS) holds 153 characters (the system reserves space for the message concatenation instruction).

Safe characters (counted as 1 character):

Type	Characters
Letters	A-Z, a-z
Digits	0-9
Symbols	@ £ $ ¥ _ ! " # % & ' ( ) * + , - . / : ; < = > ? ¡ ¿ § ¤
Greek/Other	Δ Φ Γ Λ Ω Π Ψ Σ Θ Ξ Ä ä Ö ö Ñ ñ Ü ü à ò ù å Å è é É ì ç Ø ø Æ æ ß

Note on extended characters (counted double)

The GSM-7 alphabet includes a set of characters that, although they do not switch encoding to Unicode, occupy 2 bytes. This means each of them takes up 2 characters from the available limit.

These are: ^, {, }, \, [, ~, ], |, €.

Billing Table (GSM-7):

Character Count	Billed as
1–160 characters	1 SMS
161–306 characters	2 SMS
307–459 characters	3 SMS
460–612 characters	4 SMS
613–765 characters	5 SMS
766–918 characters	6 SMS
919–1071 characters	7 SMS
1072–1224 characters	8 SMS
1225–1377 characters	9 SMS

Message with special characters (Unicode Encoding)

Using even a single character outside the GSM-7 table forces a change in the entire message encoding to Unicode (UCS-2). This is necessary for diacritics or emojis to render correctly on the recipient's phone.

What triggers Unicode encoding?

• Polish characters: ą, ć, ę, ł, ń, ó, ś, ź, ż.

• Other alphabets: Cyrillic (e.g. Б, Д, Ж), Hebrew, Arabic.

• Diacritics: Czech/Slovak (č, ž), French circumflex (â, ô), Spanish accents (á, í).

• Emoji: e.g. 🙂, 🔥, ❤️.

Unicode Limits:

• Single SMS: up to 70 characters.

• Concatenated messages: Each subsequent segment holds 67 characters.

Billing Table (Unicode):

Character Count	Billed as
1–70 characters	1 SMS
71–134 characters	2 SMS
135–201 characters	3 SMS
202–268 characters	4 SMS
269–335 characters	5 SMS
336–402 characters	6 SMS
403–469 characters	7 SMS
470–536 characters	8 SMS
537–603 characters	9 SMS

Impact of Personalization on Cost

If you use personalization tags (e.g. ##name##), the final message length will vary for each recipient. This may result in part of the database being billed as 1 SMS and another part as 2 SMS messages.

Example: Suppose your template (with special characters) has 65 characters.

• For the name "Anna" (4 chars) – total 69 characters. Fits limit 70. -> Cost: 1 SMS.

• For the name "Katherine" (9 chars) – total 74 characters. Exceeds limit 70. -> Cost: 2 SMS.

When planning a campaign, always leave a safe character margin, taking into account the longest data in your database (e.g. long surnames or city names).

Recommendation: Before sending, always verify in our panel how the system counted the characters in your message. The character counter shows in real-time how many parts the SMS will consist of, helping you avoid unexpected costs.