Why it matters
Carrier filtering impacts message deliverability. Knowing why it happens helps you prevent blocks, maintain consistent communication, and protect your sender reputation.
Key Concepts
Carrier filtering: Processes carriers use to block messages that appear risky, non-compliant, or spam-like.
Messaging policies: Requirements set by Whippy and carriers that define acceptable SMS behavior.
Delivery indicators: Status messages such as “Undelivered” that may signal filtering.
Understanding Carrier Filtering
FAQ: Why do message filtering systems exist?
Carriers filter messages to protect subscribers from spam, fraud, and abuse while enforcing regulations across regions and networks.
FAQ: How does message filtering work?
Filtering systems range from simple keyword checks to advanced machine-learning models. Carriers evaluate message content, volume patterns, URLs, sender behavior, and compliance with messaging policies. Whippy follows carrier rules, the Messaging Policy, and AUP requirements to ensure compliant sending.
Identifying When Messages Are Being Filtered
FAQ: How can I tell if my messages are being filtered?
Look for Undelivered statuses or error messages in conversations, campaigns, or sequences.
Be aware that some carriers incorrectly report filtered messages as “Delivered,” so deliverability issues may not always be obvious.
Preventing Messages From Being Filtered
FAQ: How can I prevent my messages from being filtered?
Follow Whippy’s Acceptable Use Policy and Messaging Policy.
Ensure all contacts have opted in and avoid high-risk or promotional language.
Keep accounts secure and adhere to SMS rules for each country.
Avoid repetitive, overly long, or identical messages across large audiences.
Understanding Billing for Filtered Messages
FAQ: Why am I charged for filtered messages?
Carriers still process filtered messages, even when blocked. These charges cover operational costs and help maintain secure, trusted messaging infrastructure.
Handling Incorrectly Filtered Messages
FAQ: What if my messages are being filtered by mistake?
Collect Message IDs marked as failed or undelivered.
Contact Whippy Support so the issue can be reviewed and escalated to the carrier if needed.
Tips and Best Practices
Avoid sudden spikes in message volume or repetitive content.
Send only to opted-in contacts.
Keep messages concise and compliant.
Monitor deliverability patterns to identify early warning signs.
Troubleshooting
Issue | Possible Cause | Fix |
Messages repeatedly filtered | Content violates policies or resembles spam | Rewrite content and remove risky elements |
Filtered messages show as delivered | Carrier reporting limitations | Track contact responses or engagement instead |
Still charged for filtered messages | Carrier processed message at intake | Review message strategy and optimize content |
Filtering appears incorrect | Carrier misclassification | Gather Message IDs and contact Whippy Support |