Messaging • Last Updated 2/19/2024

CTIA guidelines: Mastering messaging compliance

Learn about CTIA guidelines and how they ensure your messaging program stays compliant.

By Pete Christianson

CTIA guidelines heading

Understanding and adhering to CTIA (Cellular Telecommunications and Internet Association) guidelines is crucial for companies using business SMS messaging. Adhering to CTIA guidelines helps businesses maintain legal compliance, avoid potential fines, and foster trust among users, ultimately enhancing brand reputation.

In this post, we'll explore new and updated aspects of CTIA guidelines and provide practical tips to ensure you’re compliant.


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Understanding CTIA messaging guidelines

The CTIA is a trade association and nonprofit organization representing all wireless communications sectors, including cellular and personal communication services.

The CTIA has created guidelines, including best practices and recommendations to promote a transparent, ethical, and compliant environment for mobile messaging services. These guidelines cover content standards, consumer protection, technical requirements, and privacy regulations, ensuring businesses and marketers adhere to proper consent, opt-in/opt-out procedures, and message frequency limitations.

Contrary to popular belief, CTIA guidelines are not regulations. Instead, they’re principles and best practices that rely on voluntary compliance rather than legal enforcement. In general, the aim of both the CTIA and other organizations that regulate messaging is to protect end users from receiving unsolicited or unwanted messages via SMS.

While the CTIA won’t fine you for ignoring their guidelines, non-compliance could lead to violations of other privacy and security laws, such as the General Data Protection Regulation (GDPR) in Europe and the Telephone Consumer Protection Act (TCPA) in the U.S.

The penalties for violating those regulations can include an immediate shutdown of your messaging service or fines ranging from $500 to $1,500 per message.

By following the CTIA guidelines, mobile carriers, service providers, and businesses can maintain a positive user experience, avoid potential legal issues, and contribute to the overall growth and sustainability of the mobile messaging ecosystem.

To help you quickly grasp these guidelines, we've summarized the main definitions and best practices below.

CTIA guidelines: Common terms and definitions

Before diving into the best practices, it's crucial to understand some key terms used in the CTIA guidelines.

TermDefinition
ConsumerAn individual who subscribes to a wireless messaging service or messaging application. Consumers are not agents of businesses, organizations, or entities that send messages to consumers.
P2P (Person to Person) trafficP2P traffic occurs when low-volume messages are sent between human end-users.
A2P (Application to Person) trafficA2P traffic occurs when agents of businesses, organizations, and entities send messages to consumers. A2P messaging includes businesses of all sizes, nonprofit organizations, political campaigns, financial institutions, medical practices, schools, and customer service entities. Virtually all business SMS applications are considered A2P messages.
SMS (Short Messaging Service)SMS is used for sending text-only messages over cellular networks.
MMS (Multimedia Messaging Service)MMS is used for sending text, images, and video over cellular networks. MMS messages can include only text, but MMS is most efficient for sending images and videos.
RCS (Rich Communications Service)RCS is an advanced SMS protocol capable of sending high-resolution photos and files, processing payments, location sharing, video calling, and other high-data operations.

CTIA guidelines apply to messaging activities using SMS, MMS, and RCS for P2P and A2P traffic. Now that you understand these definitions, let’s dive into CTIA principles and best practices.

CTIA guidelines: Best practices

The CTIA guidelines are generally easy to follow. Their primary focus is on A2P traffic. The most significant recent change to the guidelines is the reclassification of some messages previously considered P2P traffic as A2P traffic.

How do I know if I’m compliant?

The new approach to A2P messaging is consent-based. Here are two best practices to ensure you’re in compliance:

  1. Always obtain a consumer's written consent before sending messages. You can obtain written consent in various ways, but you must document and keep records of all consumers who have consented to receive your messages. Customers should be aware that they’ve chosen to opt in—that is, they’ve agreed to receive your messages.
  2. Always provide consumers with an easy way to stop receiving messages. Consumers should be able to use a stop word to opt out at any time.

The CTIA recommends obtaining consent through automated mechanisms to improve the end-user experience and ensure consent is always obtained before sending A2P messages. Popular consent mechanisms include:

  • Online consent collection forms
  • One-click opt-in buttons on web pages (usually a checkbox on subscribe or check-out pages)
  • Marketing emails or social media posts that offer discounts or promotions in exchange for a customer signing up for your messaging lists
  • Asking consumers to text a word like “spring23” to your short code number

These recommended opt-in mechanisms are designed to help you get consent when collecting a consumer's phone number, minimizing the possibility of sending unsolicited messages.

What number type should I use?

Regarding the numbers you should use for sending A2P messages, the CTIA recommends using standard messaging number types such as short code, toll-free, and 10DLC.

Short code numbers

Short code numbers are perfect for sending SMS and MMS messages. Short codes are five- or six-digit numbers used for one-way A2P communication.

Toll-free numbers

Toll-free numbers are ideal for getting consumers to respond to your texts. People feel more comfortable texting a toll-free number because they know they won't get charged.

10DLC numbers

10DLC numbers are ideal when you want to use geo-matching to send messages from a phone number that matches the recipient's area code.

What’s the most important takeaway from the CTIA guidelines?

The most crucial aspect of CTIA guidelines is obtaining consumer consent before sending messages. Ensuring consumers agree to receive your messages helps you provide the best end-user experience. It also enables you to avoid being perceived as a spammy message sender. Obtaining consent—ensuring consumers have opted in—also makes it less likely that you’ll find yourself violating other regulatory laws.

By following CTIA guidelines, you protect the end-user and your reputation as an SMS sender. Talk to your legal team for more detailed information and best practices on compliance with other regulatory bodies such as GDPR and TCPA.

Frequently asked questions about CTIA guidelines

Are CTIA guidelines legally binding?

No, CTIA guidelines are not legally binding. Instead, they’re a set of voluntary principles and best practices designed to help companies comply with local and federal SMS regulations. However, non-compliance with CTIA guidelines could lead to violations of other regulations, such as GDPR or the Federal Trade Commission Act, which could result in fines.

Do CTIA guidelines apply to both SMS and MMS messaging?

Yes, CTIA guidelines apply to messaging activities using SMS, MMS, and RCS for both P2P and A2P traffic. Following these guidelines ensures your messaging programs are compliant and provide the best end-user experience.

How do I obtain consumer consent for A2P messaging?

The CTIA recommends obtaining consumer consent through automated online consent collection forms, one-click opt-in buttons on web pages, opt-in messages sent to consumer mobile devices, and phone opt-in using interactive voice response (IVR) technology. These mechanisms help ensure consent is obtained before sending A2P messages, improving the end-user experience.

Getting started with CTIA-compliant messaging

Adhering to CTIA guidelines is essential for a successful, legally compliant SMS program that delivers an excellent end-user experience. Choosing a messaging provider who can partner with you in maintaining compliance can help ensure you don’t face spam complaints, fines, or shutdowns.

Telnyx is a next-gen communications platform that provides carrier-grade services on a global private IP network. We control the network end to end, own approximately 8 million numbers, and have multi-cloud redundancy.

Our APIs are built by developers, for developers, so you can build high-quality messaging capabilities into your existing apps with ease. In addition, Telnyx provides the tools to underpin your SMS strategy, which frees you up to have engaging, insightful customer conversations. Whether you’re using messaging to improve customer satisfaction, boost conversion, increase productivity, or reduce costs, you can leverage our reliable, private network, intuitive APIs, and intelligent features to drive your business forward.

Founded in 2009, Telnyx is a licensed carrier in over 30 countries. Cutting out the middleman allows us to drive efficiencies, provide our customers with better products, and set industry standards for price, value, and quality.

Talk to an expert today to start building your ideal messaging solution and sending CTIA-compliant messages.

This blog post is not legal advice. Always consult your legal team and the appropriate regulatory authorities before using SMS or MMS messaging for your business. In the meantime, be sure to read our Compliance Guide to help demystify some additional rules and regulations surrounding business messaging.

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