Message Deliverability

Message deliverability measures the percentage of SMS messages that successfully reach recipients’ mobile devices out of the total messages sent by a business or organization.

Why Message Deliverability Matters

Message deliverability represents the fundamental metric determining whether your SMS communication strategy succeeds or fails. Unlike email where messages might land in spam folders, undelivered text messages simply disappear, creating a communication void that directly impacts business operations and customer relationships.

The business implications of poor deliverability extend far beyond wasted messaging costs. When a two-factor authentication code fails to arrive, customers abandon purchases. Missed appointment reminders lead to no-shows costing healthcare providers an average of $200 per incident. Failed delivery notifications result in customer service calls that cost 50-100 times more than the original SMS. For time-sensitive communications, even 95% deliverability means 1 in 20 critical messages fail.

Modern consumers expect instant, reliable SMS communication. Studies show 90% of text messages are read within three minutes of delivery - but only if they arrive. As businesses increasingly rely on SMS for critical workflows, deliverability becomes a competitive differentiator. Companies achieving 97%+ deliverability see higher customer satisfaction, reduced operational costs, and improved conversion rates compared to those accepting industry-average 85-90% delivery rates.

How Message Deliverability Works

Message deliverability involves a complex journey from sender to recipient, with multiple potential failure points along the transmission path. Understanding this journey helps identify optimization opportunities.

The SMS Delivery Path:

When you send an SMS, it first reaches your messaging provider’s platform, which validates the format and recipient number. The provider then routes the message to the appropriate carrier network based on number portability databases and routing tables. Each carrier processes the message through spam filters, checking sender reputation and content compliance.

Key Stages and Potential Failures:

1. Submission Stage: Your system sends to the SMS gateway

   • Failures: API errors, authentication issues, malformed requests

2. Gateway Processing: Message validation and routing determination

   • Failures: Invalid numbers, blocked senders, credit limits

3. Carrier Acceptance: Network receives and evaluates the message

   • Failures: Filtering, reputation blocks, compliance violations

4. Network Routing: Message travels through interconnected systems

   • Failures: Network congestion, routing errors, international blocks

5. Device Delivery: Final transmission to recipient’s phone

   • Failures: Device offline, storage full, number deactivated

Measurement and Reporting:

Delivery receipts (DLRs) provide status updates at various stages, though not all carriers support detailed reporting. “Delivered” status typically means carrier acceptance, not necessarily device receipt. True end-to-end confirmation requires advanced delivery receipt handling and sometimes application-layer acknowledgments.

Network conditions, carrier relationships, and technical configurations all influence deliverability. Peak traffic periods can reduce rates by 5-10%, while poor peering agreements between carriers might cause systematic failures to specific networks.

Best Practices with Message Deliverability

• Implement comprehensive number validation - Verify numbers at collection using HLR (Home Location Register) lookups to identify invalid, deactivated, or landline numbers before sending. This prevents unnecessary failures and protects sender reputation.

• Optimize message content and format - Keep messages concise, under 160 characters when possible. Avoid spam triggers like ALL CAPS, excessive punctuation, or URL shorteners. Use proper UTF-8 encoding for special characters to prevent fragmentation issues.

• Configure intelligent retry logic - Implement exponential backoff for temporary failures: retry after 1, 5, and 15 minutes. Set maximum retry attempts based on message priority. Never retry permanent failures like invalid numbers.

• Monitor deliverability by segment - Track rates separately by carrier, geographic region, message type, and time sent. This granular view reveals specific problem areas. A 95% overall rate might hide 80% delivery to rural T-Mobile customers.

• Maintain multiple routing options - Configure primary and backup routes through different aggregators or direct carrier connections. Automatic failover prevents single points of failure during carrier outages or maintenance windows.

• Build feedback loops - Create mechanisms for recipients to report non-delivery through your app or website. This catches silent failures and provides data for troubleshooting systematic issues carriers might not report.

• Schedule around optimal windows - Analyze your delivery data to identify peak performance times. Avoid carrier maintenance windows and network congestion periods. For global sending, consider recipient timezone and local carrier patterns.

Real world examples

Common misconceptions

Related terms