Klaviyo SMS Marketing: Is It Worth It? Honest Review (2026)

Last Updated: February 2026

We manage Klaviyo SMS marketing across multiple ecommerce brands. We've also managed accounts on Attentive, Postscript, and Yotpo SMSBump.

This is our honest take on Klaviyo SMS marketing — what it does well, what could be better, how pricing works, and whether it makes sense for your brand.

Short answer: If you're already using Klaviyo for email, use Klaviyo for SMS. There's almost no scenario where a dedicated SMS platform makes sense if Klaviyo is your email provider.

What Klaviyo SMS Actually Does

Klaviyo built SMS on top of their existing email marketing platform. That's the key differentiator. Everything you already use for email — flows, segments, campaigns, analytics — works with SMS too.

In practice, this means:

• Flows can mix email and SMS. Your abandoned cart flow can send an email first, then follow up with an SMS if the customer doesn't convert. Same flow, same triggers, same filters.
• Segments are shared. Any segment you build for email — repeat buyers, VIPs, lapsed customers — automatically works for SMS targeting too. No duplicate audience building.
• One dashboard for everything. Revenue attribution, deliverability, subscriber growth — email and SMS reporting in the same place. No cross-referencing two platforms.
• Shopify data flows in natively. Purchase history, browse behavior, cart data — all available for SMS personalization and triggers, just like email.

Dedicated SMS platforms like Attentive and Postscript build their own versions of flows, segments, and campaigns. But they're rebuilding what Klaviyo already has — and the integration between their SMS tools and your email platform is never as tight as Klaviyo's native connection.

Klaviyo SMS Pricing: How Credits Work

Klaviyo SMS uses a credit-based pricing model. Here's how it breaks down:

• 1 SMS credit = 160 characters. Go over 160 characters and you're using 2 credits per message.
• Images (MMS) cost more. Adding a product image turns your SMS into an MMS, which uses additional credits.
• Emojis cost more too. Emojis use Unicode encoding, which reduces the character limit per segment — meaning your 160-character message might become a 2-credit message because you added an emoji.
• Volume discounts. Per-credit cost decreases as you buy more. Pricing is tiered and transparent — it gets cheaper at scale.

For current pricing tiers, check Klaviyo's pricing page directly — they use a calculator that adjusts based on your list size and message volume.

Pricing-wise, Klaviyo SMS is competitive with Attentive, Postscript, and SMSBump. They're all roughly in the same range — credit-based, volume-discounted. The per-credit cost difference between platforms is marginal. The real savings come from not paying for a second platform and not spending operational hours managing two systems.

Setting Up Klaviyo SMS on Shopify

Klaviyo SMS setup on Shopify is straightforward, but there are things brands miss.

Collect SMS consent in two places

Most brands only collect SMS opt-ins on their popup form. You need it in both places:

1. Your signup popup. Add a phone number field (or a separate SMS step) to your email popup. This catches new visitors.
2. Shopify checkout. Enable SMS marketing consent in your Shopify checkout settings. This captures phone numbers from buyers — which is where most of your SMS list actually comes from.

If you only collect on the popup, you're missing checkout subscribers. If you only collect at checkout, you can't send pre-purchase SMS. You need both.

TCPA compliance basics

SMS marketing in the US falls under the Telephone Consumer Protection Act (TCPA). The essentials:

• Explicit consent required. You need clear opt-in before sending marketing SMS. Klaviyo handles the consent language in their built-in forms.
• Easy opt-out. Every SMS must include a way to unsubscribe. Klaviyo adds “Reply STOP to unsubscribe” automatically.
• Quiet hours. Don't send SMS before 8am or after 9pm in the recipient's time zone. Klaviyo enforces this by default — but check your settings if you're scheduling campaigns near those boundaries.

Integrate SMS into your flows

Once SMS is enabled, add it to your existing Klaviyo flows. The ones that benefit most:

• Abandoned cart / abandoned checkout — SMS follow-up after the email doesn't convert
• Shipping notifications — order confirmed, shipped, delivered
• Welcome flow — a quick SMS after signup reinforces the relationship
• Winback — SMS for lapsed customers who haven't responded to email

For copy-paste templates for each of these flows, see our SMS marketing templates guide.

When Klaviyo SMS Makes Sense (and When It Doesn't)

Use Klaviyo SMS if you're using Klaviyo for email. Klaviyo already has the flow builder, the segmentation engine, the campaign tools, and the Shopify integration. SMS is built on top of all of that. Everything the dedicated SMS platforms do — flows, audiences, campaigns — Klaviyo already does for email and has extended to SMS.

There is functionally nothing that Attentive, Postscript, or SMSBump can do that Klaviyo SMS marketing can't. And Klaviyo does it with the advantage of native data — no syncing, no integration issues, no split reporting.

The only exception: you're not using Klaviyo for email. If your email is on Mailchimp, Omnisend, or another platform and you want to add SMS, then a standalone SMS tool like Postscript might work. But if you're serious about ecommerce retention marketing, we'd recommend migrating both email and SMS to Klaviyo. The consolidated platform is worth it.

Klaviyo SMS vs Attentive vs Postscript

Here's how Klaviyo SMS stacks up against the two most common dedicated SMS platforms:

For detailed reviews: Attentive review · Postscript review · Yotpo SMSBump review

Common Klaviyo SMS Mistakes

1. Paying for it but not using it

The most common mistake we see. A brand enables Klaviyo SMS, adds it to their abandoned cart flow, and then never touches it again. No campaigns, no other flow integrations, no strategy.

If you're paying for SMS, you should be sending at least 1-2 SMS campaigns per month. You should have SMS integrated into all your major flows — not just abandoned cart but welcome, shipping, winback, and promotional flows.

2. Only collecting SMS on the popup

Your popup catches new visitors, but your Shopify checkout catches buyers. Most of your SMS list growth will come from checkout. Make sure SMS consent is enabled there too.

3. Not tracking SMS ROI

Unlike email, SMS has a real per-message cost. You need to be ROI-positive on your SMS spend. Check your Klaviyo SMS reports monthly — revenue attributed vs. credits spent. If a particular campaign or flow isn't generating positive returns, adjust your targeting or cut it.

4. Treating SMS like email

SMS is a notification channel, not a brand-building channel. Messages should be short (under 160 characters when possible), direct, and actionable. No paragraphs. No daily sends. Two to four SMS campaigns per month is plenty for most brands.

Our Rating: 4.5 / 5

Frequently Asked Questions

Is Klaviyo SMS worth it?

Yes, if you're already using Klaviyo for email. You get native integration with your flows, segments, and customer data — no third-party sync issues. If you're not on Klaviyo for email, there's no specific reason to choose Klaviyo SMS over other options.

How much does Klaviyo SMS cost?

Klaviyo SMS is credit-based. One credit covers 160 characters. Images and emojis cost additional credits. Pricing gets cheaper with volume. Check Klaviyo's pricing calculator for current rates at your list size.

Should I use Klaviyo SMS or Attentive?

If you're on Klaviyo for email, use Klaviyo SMS. Running a separate SMS platform creates data sync problems, inflated attribution, and unnecessary complexity. Read our full Attentive review for details.

Should I use Klaviyo SMS or Postscript?

Same answer. Postscript works fine as a standalone tool, but managing SMS in a separate platform means duplicate audiences, separate flows, and split reporting. Read our full Postscript review.

What's the biggest mistake brands make with Klaviyo SMS?

Paying for it but not using it. Turning on SMS, adding it to one flow, and never sending campaigns. If you're paying for SMS credits, you need to be actively sending — at least 1-2 campaigns per month and SMS in all your major flows.