Should I add SMS marketing to my Shopify brand?

When does SMS marketing make sense for a Shopify brand?

Here's what I'd want to see before adding texts:

• Your email flows are live and earning. Welcome, abandoned checkout, abandoned cart, browse abandonment, post-purchase and winback should all be running. If they aren't, start with the essential Klaviyo flows.
• You have moments that can't wait. Restocks, limited drops, new flavors, launch days, the last hours of a sale. When something sells out, the restock email is your biggest send of the month. A snack brand doing about $650K a month made $48,771 from one restock email sent to 30,498 people.
• Your customers reorder. Consumable brands have natural reasons to text: "running low?" and "your order is coming up." A subscription wellness brand I work with made $47,321 in one month from its "your order is coming up" reminder email alone, 74% of all flow revenue.
• You can afford a second bill. Texts are priced by the message, and in Klaviyo they're a separate plan from email. I compare the options in Klaviyo SMS vs Postscript vs Attentive.

When should you hold off on SMS?

I'd wait if:

• Your email flows are missing or broken. Fix the channel you already pay for first.
• Your campaigns go to everyone. If email isn't segmented, texts will be blasted too, and a phone's text inbox is a lot more personal than an email inbox.
• You don't have much to say that's urgent. If every text would just be a shorter version of your newsletter, it won't earn its cost.
• Nobody owns it. SMS needs someone writing texts, checking compliance and watching opt-outs.

What are the SMS consent basics?

This is general information, not legal advice. Talk to a lawyer about your own setup.

Here's what the official pages say:

• Email consent doesn't cover SMS. Klaviyo's help center says having consent for email does not mean you have consent for SMS. You need a specific opt-in.
• You can't require it to buy. Klaviyo says it's illegal to force someone to sign up for SMS in order to make a purchase, and that SMS consent can't appear as if it's required. The federal telemarketing rule that defines "prior express written consent" (47 CFR 64.1200) also says a person can't be required to agree as a condition of buying goods or services.
• Show disclosure language wherever you collect it. Klaviyo says to include SMS disclosure language anywhere you collect SMS consent, so people understand what they're agreeing to.
• Bought lists don't count. Klaviyo says lead generation, affiliate and purchased lists are not valid SMS consent.
• Double opt-in for cart texts. Klaviyo says double opt-in is a US carrier requirement if you plan to text in a shopping cart abandonment flow.
• Mind the clock. Klaviyo's help center notes that some countries, including the US and UK, limit the hours when you can send texts, and its general guidance is to avoid sending before 8 a.m. or after 9 p.m. in the recipient's local time. Klaviyo has quiet hours settings for flows and campaigns to help with this.

If you already collect phone numbers at Shopify checkout, Klaviyo's Shopify integration can sync people who opt into SMS in Shopify to a Klaviyo list. Klaviyo notes that consent only syncs when someone subscribes to SMS in Shopify for the first time, so check how your existing subscribers came in.

What should go in email vs SMS?

Think of email as the place for the full story and SMS as the tap on the shoulder.

Email is better for: - Welcome series, education and how-to content - Product launches with detail, photos and proof - Post-purchase and winback flows with several steps - Anything people might want to read later

SMS is better for: - Restock alerts and limited drops - Launch-day "it's live" messages - Last call on a sale that ends tonight - A short cart or checkout reminder (with double opt-in in the US) - Reorder nudges for products that run out

A simple rule I'd start with: if the message would still matter tomorrow, send an email. If it won't, a text might be worth it. And don't text everything you email. If someone gets the same message in both places on the same day, you're paying twice to annoy them once.

What does SMS marketing cost?

More than people expect, because it's priced by the message, not by the contact.

Here's how three platforms describe it on their own pages, as of October 13, 2026:

• Klaviyo. Mobile messaging is its own plan, billed separately from email. Klaviyo's help center says you have a set amount of plan spend each month, it renews monthly, and unused spend doesn't roll over. Carrier fees are bundled into your rate, and long messages get split into multiple segments, which means more cost. Klaviyo also notes that paying for SMS alone doesn't remove Klaviyo branding from your emails.
• Postscript. Its pricing page lists a Starter plan at $0 a month with a $49 monthly minimum spend and $0.009 per SMS plus carrier fees. Higher plans charge a monthly fee with lower per-message rates.
• Attentive. Its pricing page lists no dollar amounts. Pricing is based on list size and messages sent, with custom quotes.

Here's some hypothetical math. Say you text 5,000 subscribers four times a month. That's 20,000 messages. At Postscript's listed Starter rate of $0.009 plus its listed average US carrier fee of about $0.0033, that's roughly $246 a month, before any MMS or long messages that split into extra segments.

Compare that to email. On Klaviyo, a 10,000-profile email plan lists at $150 a month and includes 100,000 email sends. In this example, texting 5,000 people costs more than emailing 10,000, so every text has to earn more than an email does.

How should you start with SMS?

If you decide to add it, here's where I'd start:

1. Set up consent the right way. Separate opt-in, disclosure language, double opt-in if you'll text cart reminders.
2. Collect numbers as a second step. Ask for the email first, then the phone number, so you don't lose email signups.
3. Start with a few flows. Cart or checkout reminder, restock alert, and a reorder nudge if your product runs out.
4. Send fewer campaigns than email. Save texts for news that can't wait.
5. Measure it on its own. Revenue per subscriber, opt-out rate and whether email revenue dropped when you added texts. If email went down as much as SMS went up, you didn't grow.

Where these numbers come from

The restock and subscription reminder numbers are from individual client accounts. Platform prices and rules come from Klaviyo's, Postscript's and Attentive's own pages and the federal rule text, listed in Sources.

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WRITTEN BY Jack White

Founder of Bardown Digital, a Chicago-based Klaviyo email and retention agency for Shopify brands. He's worked with brands doing $500K to $100M a year, with $100M+ in email-attributed revenue across them.

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