Blocked by Carriers? A Business Guide to Text Message Filtering and Compliance
For any business that relies on text messaging, having your numbers blocked by major telecom carriers isn't just an inconvenience--it's a direct threat to your customer communication and revenue. Carriers are more aggressive than ever in filtering messages to combat spam, meaning legitimate businesses can easily get caught in the crossfire. Navigating this landscape requires a proactive, systematic approach grounded in both industry best practices, such as the CTIA's Messaging Principles and Best Practices, and legal requirements like the TCPA.
This guide will break down the essential steps for both immediate resolution if you've been blocked and for building a long-term strategy to ensure it never happens again.
Crisis Management: Responding to a Carrier Block
If you suspect your messages are being filtered, you must act with urgency. A carrier block is a clear sign that your sending reputation is damaged, and every delayed action makes a successful appeal more difficult.
Step 1: Stop All Sending Immediately. This is the most critical first step. Continuing to send messages from a blocked number will only compound the "carrier violations" associated with your account and severely weaken your case for resolution.
Step 2: Diagnose the Problem. Before you can fix the issue, you must identify the cause. Check your messaging platform (e.g., Twilio, Bandwidth) for delivery receipts and error codes like "carrier violation" or "spam." Then, scrutinize your message content for common red flags:
"Spammy" Keywords: Phrases that create false urgency or sound too good to be true, like "free," "winner," or "guaranteed."
Suspicious Links: Generic URL shorteners (e.g., bit.ly) are frequently flagged by carriers who see them as an attempt to obscure a link's true destination.
Aggressive Formatting: Using ALL CAPS or excessive punctuation is a hallmark of spam.
Step 3: Engage Your Messaging Partner. Your SMS aggregator is your most effective ally. They have direct relationships with the carriers and access to more detailed delivery logs. Open a support ticket immediately and provide all relevant information: the affected numbers, the time the block began, and the specific message content. They are your liaison for filing an official appeal.
Step 4: Prepare Your Case. To get your number unblocked, you must prove your legitimacy. Be prepared to provide clear evidence of express written consent for every recipient. This is non-negotiable. You must be able to demonstrate who you are, what your messages are about, and that your recipients explicitly asked to receive them.
Building a Bulletproof Texting Strategy: Proactive Compliance
Resolving a block is only half the battle. The real goal is to implement a robust compliance framework that prevents it from happening in the first place.
Master the Double Opt-In. Under the TCPA, "express written consent" is a legal requirement for marketing texts. The gold standard for achieving this is a double opt-in. After a user signs up, send an initial text requiring them to reply "YES" to confirm their subscription. Only after receiving that second confirmation should they be added to your active list. While the TCPA does not require a double opt-in, it is one of the CTIA's best practices: "After the Message Sender has confirmed that a Consumer has opted-in, the Message Sender should send the Consumer an opt-in confirmation message before any additional messaging is sent."
Make Opt-Out Effortless. Every promotional message must provide a clear and easy way to unsubscribe, typically "Reply STOP to cancel." Your system must be configured to recognize universal opt-out keywords ("STOP," "END," "UNSUBSCRIBE," etc.) and process them immediately and automatically.
Establish a Trusted Sender Identity. Your phone number is your reputation. Use a 10-digit long code (10DLC) that is officially registered with The Campaign Registry (TCR). This process authenticates your brand and your specific messaging campaigns, drastically reducing the likelihood of being flagged as spam.
Create Compliant and Engaging Content. Always identify your brand at the beginning of the message. Use your full, branded URLs instead of generic shorteners to build trust with both carriers and consumers. Finally, vary your messaging; sending the exact same text to thousands of recipients is a classic spam pattern that AI filters are designed to catch.
Key Takeaways for Long-Term Deliverability
Consent is Non-Negotiable. A verifiable record of express written consent, ideally through a double opt-in, is your single most important asset in proving your legitimacy to carriers.
Your Sender ID is Your Reputation. Registering your numbers via 10DLC is no longer optional--it's a foundational requirement for any serious business messaging campaign.
Content is Your First Line of Defense. Simple changes--like removing spammy words, using branded links, and identifying your business--can make the difference between a successful campaign and a carrier block.
The Opt-Out Must Be Universal and Instant. Ensuring consumers can easily stop messages is not just a best practice; it's a legal requirement and a key signal to carriers that you are a responsible sender.
