SMS Deliverability Best Practices

A few consistent habits make the difference between texts that land in someone's inbox and texts that get silently filtered by a carrier.

Before you send your first message to someone

• Get real opt-in consent. Never message a purchased or third-party list — consent has to come directly from the recipient.
• Reference how they opted in. Mentioning the source ("since you signed up on our site...") reassures both the recipient and carrier filters that this is expected, not random.
• Consider a double opt-in for higher-stakes campaigns — asking the recipient to reply "1" to confirm before you start a full messaging sequence.

In every first message to a new contact

• Identify your business. State clearly who's texting.
• Include opt-out instructions. Something like "Reply STOP to unsubscribe."

Ongoing hygiene

• Filter out landlines before texting. Turn on Number Intelligence to catch non-SMS-capable numbers automatically, rather than finding out from a failed send.
• Use branded links, not public shorteners — see Shortened URLs and SMS Deliverability.
• Complete A2P registration if you're messaging US contacts — see What Is A2P 10DLC?. Unregistered numbers get filtered far more aggressively.

Metrics to watch

Keep your opt-out rate under about 1% and your error rate under about 6%. Carriers monitor both, and consistently exceeding these thresholds can trigger a temporary (often 24-hour) or longer-term sending restriction. Check Messaging Analytics regularly rather than waiting for a suspension to notice a problem.