How to Get More SMS Subscribers (And What to Do About the 97% Who Won't Subscribe)

Building an SMS subscriber list is one of the highest-ROI investments an e-commerce brand can make. Once someone opts in to your texts, you have a direct line to their phone with 98% open rates and 45% response rates. The problem? Getting them to opt in is painfully slow.

Most stores convert 1-3% of their website visitors into SMS subscribers. That means for every 1,000 people who visit your site, 970+ leave without ever giving you their phone number. This guide covers the best strategies to grow your SMS list — and what to do about the vast majority who will never subscribe.

Part of our SMS Marketing Best Practices series.

Why SMS List Building Matters

Your SMS list is one of the few marketing assets you truly own. Unlike social media followers (where algorithms control reach) or paid ads (where you pay per impression), an SMS subscriber is someone you can reach directly, anytime, with near-guaranteed visibility.

The economics are compelling:

• SMS subscribers generate 3-5x more revenue per contact than email subscribers
• SMS campaigns drive immediate action — most purchases happen within an hour of receiving a text
• Retention rates for SMS subscribers are significantly higher than email-only customers

The challenge isn't whether SMS subscribers are valuable — it's acquiring them at scale.

Proven Strategies to Grow Your SMS List

1. Website pop-ups with a strong incentive

The most common acquisition tactic is a pop-up offering a discount (typically 10-15% off) in exchange for a phone number. Best practices:

• Time the pop-up — show it after 5-10 seconds or on exit intent, not immediately on page load
• Make the value clear — "Get 15% off your first order" converts better than "Sign up for texts"
• Keep the form minimal — phone number only, don't ask for name and email too
• Mobile-optimized — most of your traffic is mobile, so the pop-up must work perfectly on small screens

Expect a 1-3% conversion rate on pop-ups. That sounds low, but over time these subscribers compound into a valuable list.

2. Checkout opt-in

Add an SMS opt-in checkbox on your checkout page. Customers are already entering their phone number for shipping notifications — adding a "Send me exclusive offers via text" checkbox is low-friction. Conversion rates here are higher (5-10%) because the customer is already in a buying mindset.

The downside: only 3% of your traffic reaches checkout. You're fishing in a very small pond.

3. Cross-promote from email

If you have an email list, promote SMS sign-up through dedicated campaigns and email footers. Frame it as an upgrade: "Get flash sale alerts 2 hours before email subscribers." This works because email subscribers have already demonstrated interest in your brand.

4. Social media promotion

Use your Instagram bio, TikTok profile, and social posts to drive SMS sign-ups. A "Text JOIN to 55555" call-to-action in your bio provides a frictionless path from social browser to SMS subscriber.

5. In-store and packaging inserts

For brands with physical presence, QR codes on receipts, packaging inserts, and in-store signage can drive opt-ins. Include a clear incentive: "Scan for 20% off your next order."

6. Exclusive content and early access

Not every incentive has to be a discount. Offering SMS-exclusive access to new drops, restocks, or limited editions can attract subscribers without eroding your margins. This works especially well for brands with strong product demand.

Retaining SMS Subscribers

Growing your list means nothing if subscribers opt out after two weeks. Retention best practices:

• Limit frequency — 2-4 texts per month is the sweet spot. More than that and unsubscribe rates spike.
• Deliver real value — every message should offer something: a deal, early access, useful information. No fluff.
• Personalize — segment by purchase history and browse behavior. A returning customer and a first-time visitor should get different messages.
• Mix content types — don't send only discounts or you'll train customers to never pay full price.

The Elephant in the Room: Most Visitors Will Never Subscribe

Here's the reality that every SMS list-building guide avoids: no matter how good your pop-ups, incentives, and checkout flows are, the vast majority of your traffic will never opt in. They visit from a social media ad, browse for 30 seconds, and leave. You don't get their phone number. You don't get their email. They're gone.

This is especially painful when you're paying for that traffic. If you're spending $5,000/month on TikTok ads driving 10,000 clicks, and 200 of those become SMS subscribers, you're paying $25 per SMS subscriber. The other 9,800 clicks? Pure waste from a retention perspective.

What If You Didn't Need Subscribers at All?

The entire SMS model is built on a premise: you need contact information to follow up with a customer. But what if you could reach a shopper after they leave — without their phone number, email, or any opt-in?

Push notifications through Apple App Clips make this possible. When a shopper taps your social media ad, they land in a native iOS experience. The moment the App Clip opens, you can send push notifications for up to 8 hours — no phone number, no email, no sign-up form. If they browse and leave, you send a push notification to their Lock Screen to bring them back.

The Ideal Stack: Push for Reach, SMS for Depth

This isn't about replacing SMS — it's about covering the gap SMS can't fill:

• Push notifications reach 100% of your App Clip visitors from day one. No subscriber acquisition needed. Best for recovering browse-phase abandonment from paid traffic.
• SMS reaches your opted-in subscribers with richer, ongoing campaigns. Best for flash sales, loyalty programs, and repeat purchase flows.

Use push to capture the immediate recovery opportunity. Use SMS to build the long-term relationship. Together, they cover your entire funnel instead of just the bottom of it.

Read the full guide: SMS Marketing Best Practices for E-Commerce

Want to recover the 93% of shoppers who leave before adding to cart?