8 Biggest SMS Marketing Mistakes to Avoid (And the Best Practices That Get Results)

SMS marketing is the practice of sending short, timely and targeted promotional messages to nudge customers toward action—whether that’s grabbing a deal, finishing a purchase, or showing up to an event. It’s fast, direct, and shows up right where people pay attention: their phones. Used right, business can engage customers in real time and forge deep connections. Used wrong, it becomes noise or worse—an intrusion. That’s why a smart approach matters from the start.

Most brands spend hours crafting emails that never get opened. Meanwhile, SMS gets seen—fast. Nearly every text is read, most within a couple of minutes. It’s also one of the best tools for delivering time-sensitive information and can be used to complement other marketing channels.

Yet many businesses still aren’t using it.
That gap is a missed opportunity.

People check texts faster than email, and they don’t hand out their number unless they actually want to hear from a brand. Fewer than 5% of people ever unsubscribe from SMS lists, while 20% or more drop off email lists every year. That means less opt-outs, more engagement, and better chances to convert.

Some key benefits and stats you need to know:

Just because a contact’s phone number is on file doesn’t mean it should be used. Numbers collected at checkout, through business cards, or event sign-ups aren’t automatic permission. Unsolicited texts feel intrusive and often will get ignored or blocked. Worse, carriers may flag or permanently restrict certain marketing messages. Texting without consent isn’t just bad practice—it damages trust, tanks delivery rates, and puts campaigns at risk before they even start.

Text messages are powerful only when there’s a clear reason to send them, and permission to back it up. For example, a retail store might post a sign at checkout: “Text SALE to 7834 to get alerts on future flash sales.” Or a company that shares stock tips might use SMS to send time-sensitive updates that lose value in an email inbox. This kind of message is helpful, expected, and earns trust—because the intent is clear, and the customer chooses to receive it.

Getting permission starts with an SMS opt-in:

• A keyword like “JOIN” sent to a shortcode
• A web form asking for consent to send texts about promos or updates
• A signup at checkout offering a discount in exchange for SMS alerts

People expect control over how brands communicate with them. Clear and simple SMS opt-in and opt-out instructions empower customers to manage what they receive and keep the relationship transparent.

Opt-out options should be:

• Visible in every message
• Easy to use (e.g. reply STOP or tap a link)
• Honored immediately, with no added friction

Opt-out instructions should appear wherever someone is invited to join—whether through a keyword, form, or sign-up sheet. They should also be included in the first confirmation message after someone opts in, along with any compliance info like “message and data rates may apply” and with a link to terms. While not required in every outbound campaign, occasional reminders help maintain trust and keep your list clean.

Preference centers can also help, letting subscribers choose what kinds of texts they want to receive—if any. Respecting those choices is the foundation of sustainable SMS marketing.

If subscribers signed up for flash sale alerts, that’s all they should receive. Not product announcements, not referral programs, not general updates. On the other hand, if a weekly newsletter was promised, product promotions shouldn’t be sent to that list either. Deviating from the original message breaks trust and feels spammy. SMS isn’t the place to improvise, only send what people explicitly opted in to receive so they stick around.

SMS is designed for quick reads and should be kept within the 160 character limit. Anything longer risks being cut off, ignored, or marked as spam. Long, cluttered messages not only get broken up but loose impact fast. Every word counts. Get straight to the point, deliver value (a coupon, reminder, or update), and use active language to prompt action. It should feel like a quick nudge, not a newsletter. So make it clear, direct, and easy to absorb (even from a lock screen).

Rather than sending the same message to everyone, it’s more effective to tailor texts to the individual as much as possible. Personalized messages not only feel more relevant, they perform better. Believe it or not, most customers don’t care about the latest product release or company news. What they really want are messages that offer something directly beneficial to them.

The first step is audience segmentation. When SMS campaigns are sent to a broad, unsegmented list, they lose relevance—and with it, engagement. Start with basic demographic data like location or gender to form broad groups, then narrow down using behavioral and interest-based data such as purchase history or engagement level. The more specific the segment, the more relevant the message, and the better the results. It’s also important to review and update segments regularly to reflect changing customer behavior. Then, focus on personalization.

On the very basic level, use the recipient’s name—a small gesture that grabs attention. For deeper personalization, SMS can reflect interests or past behavior. For example, a limited-time offer based on recent browsing activity or a discount tied to previous buying behaviour makes the message feel intentional, not random. What are customers getting out of the message? If it’s not something worth their time, brands risk losing interest—and possibly even the subscription.

Including incentives like early-access content, VIP programs, or behind-the-scenes updates gives people a reason to stay connected. Even a birthday message with a personalized offer can create a moment that leaves a lasting impression. Strong SMS marketing starts with strong copy, written in the language the audience actually uses.

Messages should feel human—not robotic or copied from a landing page. A conversational, friendly tone works best, with no jargon or overly promotional brand language. The goal isn’t to hide that it’s a promotional message, but to avoid being too abrasive about it.

Most subscribers won’t have the number saved, so including the brand name is key. And the tone should stay consistent with how the brand communicates on other channels. If emails are casual, texts should match that. A little brand personality or humor can make a simple message feel more like a one-on-one conversation than a campaign.

A text in the middle of the night promoting a product is a fast way to lose a customer for good. Sending messages at the wrong hour can lead to missed opportunities, low engagement, or outright frustration. Not everyone’s on the same schedule, especially across time zones. Mastering timing takes data. It requires tracking when different audience segments are most likely to open and respond. The goal is to build a data-driven view of customer habits so messages land at just the right moment.

Whether sending to a global audience or a local customer base, timing plays a big role in the success of an SMS campaign.

For global audiences, it’s important to use a provider that can deliver messages in the correct local time zones and stay compliant with country-specific mobile regulations. Nobody wants a 1 AM text. The right provider should automate SMS delivery based on region, helping campaigns scale without disrupting customer schedules.

For local audiences, timing matters just as much. SMS messages should be sent when people are most likely to engage—usually before work, during lunch breaks, or early in the evening. As a general rule, avoid sending texts before 9 AM or after 9 PM.

It’s also worth considering other factors, like holidays, peak hours, or industry-specific behavior. For example, real estate or recruiting audiences may be more responsive outside typical business hours, while most B2C promotions perform better during the day.

A clear strategy keeps SMS messaging consistent and intentional. Planning ahead helps space out texts in a way that feels balanced and avoids overwhelming customers. Calendars can be used to map out scheduled sends. It’s the easiest way to track timing, avoid overlap, and maintain a steady rhythm.

Just because SMS has a high open rate doesn’t mean every message will get the same response. Some brands overdo it, sending one message after another with the hope of staying top of mind—but end up driving subscribers away.

Texting is more personal than email. It's more immediate, more visible, and a lot more interruptive. Too many texts can quickly feel spammy, and subscribers will opt out if it starts to feel like a constant stream of noise.

The frequency will depend on each brand’s SMS marketing strategy and how much value each message provides. “Less is more” is a good rule of thumb, though.

Research shows that nearly all SMS users have felt annoyed by marketing texts at some point—and the top complaint is being contacted too often. As much as SMS can build closeness, it still needs boundaries.

SMS shouldn’t be sent on a whim. Just like email, it needs structure. In most cases, limiting texts to once or twice per week is enough to keep engagement high without annoying the audience or damaging brand reputation.

When it comes to frequency, quality should always come before quantity. The goal is to find a cadence that delivers value without overwhelming subscribers. Finding that sweet spot depends on the business model, audience preferences, and industry norms. Brands should test different sending frequencies and track engagement to see what performs best. Most subscribers are already seeing brand messages in other places—email, social media, paid ads, app notifications. To avoid fatigue, there should be a clearly defined purpose for each channel, and SMS should be used intentionally as part of the broader strategy.

Sending messages to invalid or outdated numbers is one of the most common causes of SMS delivery issues. If a number has been changed, deactivated, or was fake to begin with, the message won’t reach anyone. Over time this can damage sender reputation and lower overall deliverability.

Every message sent to an inactive number is wasted budget and effort. Worse, if a number has been reassigned and consent isn’t reconfirmed, it could open the door to compliance risks under regulations like GDPR and TCPA.

The best way to avoid deliverability issues is to build an SMS list organically. Purchased or borrowed lists are risky—they often include fake, outdated, or unverified contacts.

Existing email bases should be used to invite opt-ins, and grow lists through incentives like exclusive discounts, contests, or multi-channel marketing. To reduce the chances of texting inactive numbers, regularly cleaning and updating lists is essential. Implement phone number validation through a reliable SMS API with number lookup capabilities. Reconfirm consent periodically to ensure compliance and maintain a healthy, engaged list.

Some brands lean too heavily on SMS and use it to replace email entirely. Others neglect SMS altogether and miss out on its power as a fast, personal communication tool.

Either approach is a mistake. Email and sms marketing serve different purposes and should work together to create a more seamless customer experience. Treating them as separate—or worse, competing—channels limits the full potential of both.

Another mistake is copying the same message into both SMS and email. While it may save time, it ignores the strengths and limits of each channel. SMS and email serve different purposes. Using the same format for both can make messages feel mismatched or ineffective. SMS is built for urgency and brevity, while email supports longer-form content with visuals and links.

Each channel plays a different role in your marketing strategy. SMS is great for timely reminders, quick nudges or promotions, and personal or time-sensitive updates. Email is better for longer, more visual content, confirmations, or detailed offers. Social helps extend your reach and visibility.

For example, an appointment confirmation can be sent via email, followed by a same-day reminder through SMS. Or a new product launch might be teased on social media, announced in email, and promoted via text with a time-sensitive offer.

Coordinating messaging across all three channels helps improve recall and increases the chances of conversion. The more touchpoints customers see, the more likely they are to act. Whenever possible, sync your contact lists across tools to streamline messaging.

Platforms like Marketune bring email marketing, SMS marketing, and social media marketing into one place. With built-in automation software and cross-channel coordination, it's easier to stay connected and run seamless campaigns across every touchpoint.

Crafting and sending SMS messages is only the beginning. The bigger mistake is failing to track performance or listen to feedback after messages go out. Without metrics like open rates, click-throughs, or conversions, it’s hard to know what’s working. Overlooking customer feedback can also make messages feel one-sided. And skipping A/B testing limits your ability to optimize results over time.

Use tools like Marketune’s analytics and reporting features to track performance in real time and uncover trends—what types of messages resonate, which CTAs perform best, and what send times drive engagement.

Create space for feedback. Two-way messaging builds stronger relationships and shows customers their input matters. If enabled, be ready to respond promptly.

Finally, embrace A/B testing. Test one variable at a time—like timing or CTA wording—and send variations to randomized groups to identify top-performing messages and improve future campaigns.

Getting a new subscriber is only the first step. A common mistake in SMS marketing is failing to lay the groundwork for ongoing communication. When brands skip the welcome message or delay follow-up, customers can forget why they signed up—leading to confusion, frustration, or quick unsubscribes when messages start arriving.

Not having a system in place for future contact also makes it harder to manage replies, schedule messages, or track interactions. Without clear expectations or organization, the customer experience suffers and so does campaign performance.

A welcome text should be sent immediately after subscription to confirm opt-in, set expectations, and begin the relationship on a positive note. With Marketune, it’s possible to automate welcome messages, create workflows triggered by subscriber actions, and sync contact lists to streamline SMS campaigns across channels. SMS blocks can be easily added to automations with precise conditions and timing to ensure messages reach the right people at the right time.

SMS automation saves time, reduces error, and helps keep audiences engaged. It also allows for more effective response management—ensuring no message goes unanswered and all subscriber interactions are recorded and organized. Manual sends and disorganized communication are no longer a concern. Marketune makes SMS marketing simpler, smarter, and more scalable—with all the tools, help articles, and support needed to keep growing.