The 3,072 figure gets quoted a lot, and it is the wrong number to plan around. On SMS, anything past 160 characters splits into multiple segments, each billed separately and each capable of arriving out of order. In the US an RCS text is billed the same way, per 160-byte segment, so a 400-character text costs three segments on either channel. Where RCS changes the picture is the rich card: it is billed once as one Rich Media message whatever text it holds, so detail belongs on the card, not in a long text.
The limits worth writing down
- Text message body: billed per 160-byte segment in the US, so plan on 160; Google's specification allows up to 3,072 characters in one message.
- Total message payload: 250 KB.
- Media file: 100 MB.
- Rich card title: 200 characters.
- Rich card description: 2,000 characters.
- Suggestion label: 25 characters.
- Suggestions per rich card: 4.
- Suggestions per text message: 11, counting any persistent suggestions.
- Cards in a carousel: 2 to 10.
The suggestion label limit at 25 characters is the one that bites in practice. It is short, it is counted including spaces, and truncation on a narrow handset is ugly. Write button labels first and the message body second, not the other way round.
Why the SMS comparison is misleading
A 160-character SMS is not a limit on what you can send, it is a limit on what you can send in one billed unit. Longer texts are concatenated, and the encoding matters: switching from GSM-7 to UCS-2, which a single emoji or curly apostrophe will do, drops each segment from 160 characters to 70. That is why an innocuous copy edit can quietly triple the cost of a campaign.
The 70-character emoji cliff does not apply to RCS, which counts bytes rather than switching encodings, but the segment maths does: a US RCS text is billed per 160-byte segment, so a longer text costs more segments on either channel. RCS vs SMS covers the rest of the differences, and how much RCS costs has the published rates.
Just because you can does not mean you should
Even where the protocol allows a long message, almost nothing in a business message should run past a segment or two. The messages that perform are short, and the reason is structural rather than stylistic: an RCS message is read in a notification and a thread, on a phone, usually in a few seconds, and the action lives in a button rather than in the prose.
A workable shape for most sends is two or three sentences of context, one image if it genuinely adds information, and one primary suggestion. If the content will not compress to that, the message is usually the wrong artefact and the right one is a message that links into an authenticated page or a longer document.
Where the extra room does earn its keep is in the rich card description, which can carry the detail that would otherwise force a second message: terms, a delivery window, a full address, a list of what is included. Putting that on the card rather than in a follow-up keeps the thread clean and keeps the billing to one message.
- Plan on 160 characters a segment for RCS text in the US, the same as SMS; the 3,072-character figure is Google's protocol limit, not how US carriers bill it.
- The full message payload is capped at 250 KB, and media files at 100 MB.
- Rich cards allow a 200-character title, a 2,000-character description, and four suggestions.
- Suggestion labels are limited to 25 characters, which is the constraint most likely to force a rewrite.
- The SMS encoding cliff, where one emoji cuts a segment from 160 to 70 characters, does not exist on RCS, but a long text still costs more segments.