Outbound SMS Best Practices: 12 Rules for High Deliverability

Outbound SMS has the best open rates in marketing — when it's delivered. Get these 12 rules right and your messages land. Skip them and you're paying to text a void.

1. Register for 10DLC. Unregistered traffic gets throttled and blocked. This is the floor.
2. Include opt-out language in every message. "Reply STOP to opt out." Every time.
3. Honor opt-outs instantly. STOP means stop, permanently and immediately.
4. Warm new numbers. Ramp volume gradually so reputation builds.
5. Rotate numbers. Never torch a single long code with all your volume.
6. Avoid trigger words. No "guaranteed," "act now," "free money," "$$$," or ALL CAPS.
7. Keep it short. One idea, one question, under 320 characters.
8. Lead with a question. Questions get replies; pitches get ignored.
9. Personalize. First name and a relevant detail lift response rates.
10. Respect quiet hours. No marketing texts before 8 AM or after 9 PM local time.
11. Test and score copy. Run every campaign through a red-flag scanner before sending.
12. Track deliverability. If reply rates drop, your reputation is slipping — investigate.

The hidden cost of ignoring these

Unregistered, keyword-heavy, non-compliant texts don't just fail — they train the carriers to distrust your number. Deliverability collapses for all your messages, even the good ones.

Score your copy free

Paste your SMS into our 10DLC Spam Score scanner to see exactly which rules you're breaking, then read The Autonomous Pipeline for the full compliance playbook.