An SMS is not measured in words, and the limit is not a round number someone chose. It comes from the GSM standard: a single message carries 1,120 bits. How many characters that buys depends entirely on which alphabet your text uses.
The two alphabets
Plain English text is encoded with GSM-7, which packs each character into 7 bits. That gives you 160 characters in one message. The moment your text contains a character outside that set, the whole message switches to UCS-2 at 16 bits per character — and the limit drops to 70.
What happens past the limit
Longer messages are not rejected. They are split into parts, sent separately, and reassembled by the handset — the recipient sees one message. But each part carries a small header saying how it fits together, which eats into the space, and each part is billed.
| Alphabet | Single message | Each part when split |
|---|---|---|
| GSM-7 (plain text) | 160 characters | 153 characters |
| UCS-2 (accents, emoji, non-Latin) | 70 characters | 67 characters |
So a 161-character plain message costs two, not one — and gives you 306 characters of room, not 320. A 200-character message is still two parts. There is no partial billing.
Characters that quietly cost extra
A handful of characters are in GSM-7 but take two slots instead of one, because they are stored as an escape sequence:
- The square brackets [ and ]
- Curly braces { and }
- The backslash \ and the tilde ~
- The caret ^ and the vertical bar |
- The euro sign €
None of these will break a short message, but in something already close to 160 they are the reason a message you counted as fitting does not.
Staying inside one message
- Type apostrophes and quotes directly rather than pasting from a word processor, which substitutes curly versions.
- Skip emoji in bulk sends — a single emoji forces the entire message to UCS-2 and a 70-character limit.
- Drop "Dear customer," and similar openings. The sender ID already says who you are.
- Write the link, not the explanation of the link. A shortened URL saves more characters than any amount of rewording.
- Cut "please note that", "we would like to inform you" and "kindly be advised" — they are pure padding.
The composer counts characters and parts as you type, so you can see exactly where a message tips over before you send it.