SMS compliance in 2025

SMS is a powerful tool for business. With open rates of 98% (and 90% of those messages read within three minutes), texting remains one of the fastest and most effective ways to reach customers

But the rules have changed. Carriers are enforcing stricter requirements, and global regulations are becoming more complex. A single non‑compliant message can block your campaign or lead to more dire consequences. At the same time, users still expect fast, reliable SMS. They won’t tolerate failed texts or unclear opt‑in processes.

In 2025, U.S. wireless carriers can suspend or deactivate non‑compliant messaging campaigns without warning, making compliance a prerequisite for deliverability and trust. For international senders, compliance is equally critical as regional rules tighten and enforcement rises.

Understanding SMS compliance in 2025 means learning the fundamentals to scale your messaging safely and effectively.

In this post, we’ll explain the impact of SMS compliance, what’s changing, and how to stay ahead, whether you’re texting in the U.S., Canada, Europe, or beyond.

What is SMS compliance?

SMS compliance involves adhering to the laws, regulations, and carrier guidelines governing business messaging. That includes sending messages to people who have explicitly agreed to receive them, using clear language and trustworthy content.

Following compliance rules enhances your deliverability, protects your brand reputation, and reduces legal risks. Ignoring these rules can lead to message filtering, campaign shutdowns, and even hefty fines.

In the U.S., enforcement involves multiple players, including mobile carriers, The Campaign Registry (TCR), the CTIA, and regulators such as the FCC and FTC. Globally, regulators like the ICO (UK), the CRTC (Canada), and data protection agencies across the EU play similar roles.

Major components of SMS compliance in 2025

Understanding the key elements of SMS compliance is essential for businesses aiming to meet global regulatory requirements. From obtaining consent to adhering to content guidelines, each component helps ensure that SMS campaigns are both effective and compliant.

Consent and opt-ins

Before sending any message, you need clear, documented proof that the recipient has opted in. That consent must be unambiguous and verifiable, whether collected via a web form, keyword response, or written agreement. In some markets, a double opt-in is the standard.

Message transparency

Your messages must clearly identify your business and state the purpose of the communication. If the campaign involves recurring messaging, recipients should be aware of what to expect.

Timing and frequency restrictions

Most countries enforce specific “quiet hours” for SMS marketing. For example, in the U.S., federal TCPA rules prohibit promotional texts outside 8 a.m. to 9 p.m. local time. Even when messages fall within legal hours, over‐messaging can erode trust, so be strategic about frequency, and consider local norms or carrier-level limits.

Content rules (SHAFT)

Messages containing references to sex, hate, alcohol, firearms, or tobacco (SHAFT) are restricted or outright banned in many jurisdictions. While SHAFT is a U.S. carrier acronym, similar restrictions on these categories apply in most global markets, even if they’re not labeled the same way.

Even if legal, SHAFT content may be flagged and filtered by carriers' automated systems. Campaigns touching these categories often face increased vetting requirements, so it’s important to be aware of any restrictions that apply to your messaging type.

Campaign and brand registration

In the U.S., all A2P SMS sent over 10-digit long codes (10DLC) must undergo a formal registration process with The Campaign Registry (TCR). This means you need to submit your brand profile and register each campaign’s use case before you can send messages. Toll-free and short-code numbers have their own approval workflows, although they operate under different compliance models.

Globally, 10DLC isn’t required. Instead, some markets require you to register specific elements—such as pre‑approving sender IDs, message templates, or traffic use cases—with carriers or regulators. The requirements vary widely from country to country.

Record-keeping obligations

You must maintain internal records to demonstrate compliance in the event of audits or disputes. This includes opt-in logs, consent timestamps, campaign metadata, and delivery history. These records aren’t just useful for regulators—they’re essential for debugging delivery issues and defending your sender reputation.

Choosing the right U.S. messaging path

U.S. carriers are enforcing stricter standards than ever. Whether you're using 10DLC, short code, or toll-free numbers, your campaign’s success depends on choosing the right delivery path and aligning it with your volume, use case, and compliance maturity.

Why 10DLC matters for U.S. messaging

10DLC is now the standard for most U.S. business messaging. It uses local phone numbers and is designed for verified A2P (application-to-person) traffic. Carriers reward properly registered campaigns with better deliverability—but they also enforce stricter oversight.

To send over 10DLC, you must register:

• Your brand (legal entity)
• Each campaign’s use case
• A clear, verifiable opt-in flow

Registration is not a formality. Campaigns without a clear purpose or that don’t align with CTIA guidelines can be rejected or silently filtered. And non-compliant traffic can be blocked without notice, even if you’ve completed the paperwork.

What’s changing with registration and filtering in 2025

Carriers are enforcing tighter rules with less room for error:

• Campaign denials are more frequent
• Filtering happens faster, especially for high-risk content
• Vague use cases, missing opt-in details, or sudden traffic spikes can trigger suspensions

Deliverability issues are becoming more common, and carriers rarely explain why messages are blocked. That’s why proactive compliance, detailed documentation, and continuous monitoring are essential.

How short code and toll-free options stack up

Short codes and toll-free messaging offer alternatives to 10DLC, each with unique benefits and trade-offs.

Short codes are ideal for large-scale or recurring campaigns but require significant lead time and investment. Toll-free numbers are easier to provision and budget-friendly, but still require verification and share many compliance expectations with 10DLC.

How to protect deliverability in the U.S.

Choosing the right route is the first step. But in 2025, approval doesn’t guarantee delivery. Even compliant messages can be filtered if your opt-ins are vague, campaign metadata is incomplete, or your traffic pattern raises flags.

To safeguard deliverability:

• Maintain crystal-clear opt-in flows
• Submit detailed campaign information
• Keep brand records current
• Monitor message status in real time

When delivery issues arise, visibility is key. Without it, you're left guessing while your messages silently fail.

Global SMS compliance: Why U.S. best practices aren’t enough

While U.S. compliance relies heavily on centralized systems and registration portals, international messaging requires more localized workflows and proactive filtering management. Following U.S. best practices alone isn’t enough—other regions have their own rules, carrier workflows, and cultural expectations that directly impact deliverability.

Unlike the U.S., which uses a centralized system like TCR to manage brand and campaign registration, many markets take a more fragmented approach:

Sender ID registration

In many countries across EMEA, APAC, and LATAM, businesses must pre‑register their sender IDs before sending traffic. This process verifies your brand and the alphanumeric sender name that appears on recipients’ phones. Registration is typically done with local carriers and can take anywhere from a few days to several weeks, depending on the market. Until approved, your messages may be blocked outright.

Pre‑vetting and whitelisting

Some markets, including the UK, India, and select APAC countries, require you to submit message templates, sample traffic, or additional brand documentation for pre‑approval. These pre‑vetting requirements are designed to reduce spam and abuse. Campaigns that haven’t been whitelisted by carriers may be filtered or rejected, even if the content itself is legally permissible.

Carrier‑managed filters

Carrier‑managed filtering is common worldwide, but in many EMEA and APAC regions it can be especially strict. Carriers often block or silently filter traffic they consider suspicious based on volume spikes, content patterns, or lack of proper registration. These systems are usually opaque, and unlike U.S. TCR‑linked error codes, you may not receive clear feedback when messages are dropped.

These variations mean that following U.S. playbooks won't guarantee delivery abroad. Instead, companies need localized workflows, proactive monitoring, and region-specific compliance strategies.

Building a truly global compliance strategy

To build a scalable international messaging program, you need a strategy that addresses the unique risks in each region. Here’s how to design a strategy that meets your needs:

Work with providers who manage local workflows

In markets that require alphanumeric sender ID registration (common in EMEA, LATAM, and parts of APAC) or pre‑approval of message templates and whitelisting (as seen in the U.K. and India), a local presence is essential.

Choose messaging partners who can navigate these regional requirements, submit documentation on your behalf, and help avoid delays or rejections due to missing filings or incomplete approvals.

Maintain clear opt‑in/opt‑out flows

With many regions applying stricter interpretations of consent—such as GDPR-level opt-in standards in the E.U.—vague or implicit opt-ins can trigger filtering or lead to compliance violations. Build flows that support verifiable, unambiguous consent and maintain logs of opt-in timestamps, methods, and the original opt-in language for every campaign.

Monitor delivery data closely

Carrier-managed filtering is common worldwide, but particularly prevalent in the EMEA and APAC regions. These filters often block traffic silently, with little to no feedback when messages are dropped. By monitoring real-time delivery receipts, webhook responses, and granular carrier error codes (where available), you can spot problems early and address compliance issues before they escalate.

Train your team on regional content risks

Just because content is permitted in the U.S. doesn’t mean it will pass abroad. Messages involving SHAFT-related topics, gambling, or political references may be restricted or require template pre-vetting and whitelisting in many regions. Training your team to understand these local sensitivities helps avoid unintentional violations and ensures faster approvals where required.

By understanding these differences and planning for country‑specific workflows, you can avoid the most common delivery pitfalls and maintain compliance globally.

Scale compliant messaging with Telnyx

SMS compliance is non‑negotiable in 2025. Carriers are enforcing stricter rules, and global regulations continue to evolve. Staying compliant is essential for maintaining deliverability, preventing disruptions, and building trust with your audience.

Telnyx makes compliance easier by combining flexible registration tools with deep visibility into your traffic. Our self‑serve 10DLC portal lets you register brands and campaigns directly—without relying on aggregators—and track approval status in the same dashboard you use to send messages. For toll‑free and international traffic, we support sender ID verification and pre‑registration requirements in key markets, so you know exactly what’s needed to keep messages moving.

Beyond registration, the Telnyx Messaging API provides real-time delivery insights and error codes that help pinpoint compliance-related issues before they escalate. Webhooks and granular carrier response data let your team identify when a message was filtered, delayed, or rejected and take action promptly. You can also attach campaign metadata and opt‑in proof at the API level, making it easier to demonstrate compliance with CTIA, TCR, and global standards.

Whether you’re operating in the U.S. or across multiple regions, Telnyx gives you the transparency and infrastructure needed to adapt as regulations change and continue delivering messages at scale.