Who This Is For / When to Use
Businesses sending SMS through Kyrios Phone Service
Accounts experiencing undelivered SMS or error code 30007
Users setting up SMS workflows, campaigns, or automations
Teams preparing compliance documentation for SMS approval
What Message Filtering Is
Message filtering occurs when SMS messages are blocked by carriers or Phone Service due to policy, compliance, or regulatory issues.
Filtering is used to:
Protect recipients from spam, fraud, or abusive messages
Enforce carrier, country-specific, and regulatory SMS rules
If filtering occurs, your account may temporarily lose SMS sending ability.
Signs Your Messages Are Being Filtered
You may see one or more of the following errors:
Undelivered messages with error code 30007
“Lead Connector returned Unauthorized”
“Failed to retrieve Phone Numbers”
SMS sending disabled for 24 hours
Common Causes of SMS Filtering
Filtering usually happens for one or more of these reasons:
Messages flagged as spam or unsolicited
Missing or unclear opt-in consent
No opt-out language in the first message
High opt-out rate (above 2%)
High delivery error rate (above 12%)
Prohibited or misleading message content
Non-compliant Privacy Policy or Terms pages
Required: Proper SMS Opt-In Setup
You must collect explicit SMS consent before sending any message.
Web Form Requirements
Your opt-in form must include:
A separate, optional checkbox for SMS consent
Clear explanation of message type and frequency
Opt-out instructions
Help instructions
Privacy Policy and Terms links
Example Consent Text:
“I consent to receive marketing SMS messages from COMPANY_NAME at the number provided. Message frequency varies. Message & data rates may apply. Reply STOP to unsubscribe. Reply HELP for help.”
Required: Privacy Policy Compliance
Your Privacy Policy must not state that SMS data is shared, sold, or distributed for marketing purposes.
Required Privacy Policy Statement
Your Privacy Policy must include this statement exactly or in equivalent language:
“Mobile information will not be shared with third parties or affiliates for marketing or promotional purposes. Sharing of information is allowed solely with subcontractors providing support services, such as customer service. All other use cases exclude the sharing of text messaging opt-in data and consent; this information will not be disclosed to any third parties.”
Disallowed Language
Remove or revise any references to:
“Sharing” mobile data for marketing
“Selling” leads or contact data
Affiliates receiving SMS opt-in data
Required: First Message Compliance
The first SMS message sent after opt-in must:
Identify your business
Reference the opt-in
Include opt-out instructions
Compliant Example
“David, this is Kate from ABC Company. Thanks for opting in to receive SMS notifications. I’ve reserved your appointment for Thursday at 4:00 PM. Reply STOP to unsubscribe.”
Non-Compliant Examples
Cold outreach messages
Real estate or financial solicitations without consent
Government benefit claims
Urgent or misleading offers
Incentive-based spam language
Workflow Best Practices
When using workflows or campaigns:
Ensure the first SMS step is compliant
Avoid sending SMS from multiple numbers excessively
Do not delay opt-out language until later messages
Message Content Best Practices
To reduce filtering risk:
Avoid emojis, excessive punctuation, or ALL CAPS
Use branded URLs instead of public link shorteners
Send messages relevant to the original opt-in
Avoid prohibited industries or claims
Keep messages short and conversational
Monitoring Key Metrics
Opt-Out Rate
Healthy: 0–1%
Warning: 2% → SMS sending disabled for 24 hours
Delivery Error Rate
Healthy: 0–6%
Warning: 12% → SMS sending disabled for 24 hours
High rates indicate spam complaints, invalid numbers, or carrier blocking.
What To Do If Your Account Is Filtered
If you believe filtering was applied incorrectly:
Collect at least 3 Message SIDs
Ensure each message shows:
Status: Undelivered
Error Code: 30007
Contact Kyrios Support with the Message SIDs
Request compliance review by the Compliance team
Why Filtering Systems Exist
Filtering protects:
Mobile subscribers from spam and fraud
Carrier networks from abuse
Legitimate businesses from declining SMS trust
Filtering also enforces:
Country-specific SMS laws
Carrier messaging restrictions
A2P 10DLC regulations in the United States
FAQ
What is message filtering?
Message filtering is when carriers or Phone Service block SMS messages due to spam detection, compliance issues, or regulatory violations.
How can I prevent my SMS from being filtered?
Ensure proper opt-in consent, include opt-out language, follow content guidelines, and maintain compliant Privacy Policy and Terms pages.
What does error code 30007 mean?
Error code 30007 indicates a carrier-level filtering event caused by policy violations, suspicious content, or poor sending reputation.
What opt-out rate is considered acceptable?
A healthy opt-out rate is 0–1%. Rates above 2% trigger temporary SMS suspension.
What is snowshoeing?
Snowshoeing is sending messages across many different phone numbers to avoid volume limits. This behavior is detected and leads to filtering.