SMS Marketing for Ecommerce: The Complete Guide (2026)

SMS marketing is sending promotional and informational text messages to people who have opted in to receive them. For an ecommerce brand, that means two things: automated texts triggered by what a customer does (joins your list, abandons a cart, runs low on a product) and scheduled campaigns (launches, sales, early access). Done well, it’s the fastest channel you own. Done badly, it’s the fastest way to lose a subscriber.

This guide covers how text message marketing works for online stores in 2026: the rules, the costs, the flows worth building first, and the mistakes that burn lists. It’s written from running SMS programs in Klaviyo for ecommerce brands, and every platform price and legal rule referenced is checked against the source as of September 2026.

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What is SMS marketing?

SMS (Short Message Service) marketing is permission-based marketing by text message. A subscriber opts in, usually on a website pop-up, at checkout or by texting a keyword, and the brand sends them texts about offers, launches, their cart or their order. “Text message marketing”, “text marketing” and “SMS marketing” all mean the same thing.

Three message formats sit under the same umbrella:

Format	What it is	When to use it
SMS	Plain text, 160 characters per segment (70 if it contains an emoji or special character)	Almost everything: flows, campaigns, reminders
MMS	Adds images, GIFs and longer text; costs several times more per message	Launches and products where the visual sells
RCS	The rich upgrade: branded sender, images, buttons and carousels, falling back to SMS where unsupported	Growing in the US, UK and Europe in 2026; still an upgrade, not a replacement

What makes SMS different from email isn’t the length. It’s the placement. A text lands on the lock screen alongside messages from friends and family, and it gets read almost immediately. That attention is the whole value of the channel, which is why wasting it on messages that aren’t urgent or useful is so expensive.

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How SMS marketing works for an ecommerce brand

Every SMS program has five working parts:

1. Consent. Subscribers opt in through a form, checkout checkbox or keyword, with a disclosure explaining what they’ll get, how often, and how to stop. No consent, no program.
2. A sending number. In the US that’s a toll-free number, a 10DLC local number or a short code, each registered with carriers. In the UK and Australia it’s often a branded sender ID (your brand name) or a local number.
3. A platform connected to your store. The platform needs your store’s events (viewed product, started checkout, placed order) so texts can trigger on behaviour and segments can use purchase history.
4. Messages. Automated flows, scheduled campaigns, transactional updates and, increasingly, two-way conversations.
5. Measurement. Revenue per message against the cost of sending, and the unsubscribe rate per send.

The types of message you’ll send break down like this:

Type	Examples	Consent needed
Flows (automated)	Welcome, abandoned cart, browse abandonment, back in stock, replenishment, win-back	Marketing consent
Campaigns (scheduled)	Launches, sales, early access, VIP offers	Marketing consent
Transactional	Order confirmation, shipping, delivery updates	Consent to the order updates, with no marketing in the message
Conversational	Replies, product questions, reply-to-buy, quizzes	Depends on content; marketing replies need marketing consent

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Is SMS marketing effective?

Yes, when the program is built around flows and permission rather than broadcasting.

The most useful public numbers come from Klaviyo’s SMS benchmarks. Its 2026 SMS benchmark report, drawn from more than 183,000 Klaviyo customers, found that SMS flows were 7.6% of SMS sends but drove 45.2% of SMS revenue. Klaviyo’s help centre also publishes performance tiers for US SMS campaigns (updated October 2025, and it notes ranges vary by industry):

Metric	”Good” range	”Great”
Click rate	8.9% to 14.5%	14.6% or more
Conversion rate	1.0% to 2.0%	2.1% or more
Unsubscribe rate	0.6% to 1.4%	Below 0.5%
Revenue per recipient	$0.66 to $2.41	$2.42 or more

A word on the “98% open rate” you’ll see on almost every SMS page: SMS platforms can’t track opens the way email does, so treat it as a claim about attention, not a metric you can measure. Judge your program on clicks, orders, revenue per message and unsubscribes.

The honest version of effectiveness: SMS amplifies intent. A back-in-stock text to someone who asked to be told converts brilliantly. A fifth discount text of the month to your whole list converts a little, and costs you subscribers who would have bought later.

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Is SMS marketing legal? The rules in brief

SMS marketing is legal with consent, and it’s the most regulated channel you’ll run. In brief:

• US: TCPA and FCC rules. Marketing texts sent with an autodialer need prior express written consent. Opt-outs (stop, quit, end, revoke, opt out, cancel, unsubscribe, or anything that reasonably means stop) must be honoured within 10 business days. Telephone solicitations are barred before 8 a.m. and after 9 p.m. in the recipient’s time zone. Statutory damages are $500 per text, up to $1,500 if willful, under 47 U.S.C. § 227.
• US: states and carriers. Florida and Oklahoma limit sending to 8 a.m. to 8 p.m. and cap repeat solicitations. Carriers require sender registration (10DLC, toll-free verification or short code approval) and enforce CTIA’s opt-in and opt-out standards.
• Australia: Spam Act 2003. Consent, clear sender identification and a working unsubscribe honoured within five working days. Since 1 July 2026, texts from business-name sender IDs that aren’t on the ACMA’s SMS Sender ID Register show as “Unverified”.
• UK: PECR. Prior consent, with a narrow soft opt-in for existing customers buying similar products. Since February 2026, fines can reach £17.5 million or 4% of worldwide turnover.

The full detail, with links to the FCC, CTIA, The Campaign Registry, the ACMA and the ICO, is in our SMS marketing compliance guide.

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How much does SMS marketing cost?

SMS is priced per message, which makes it different from email. Most ecommerce platforms charge a per-message rate, sometimes on top of a monthly platform fee, and carrier fees are either built in or passed through.

As of September 2026, published US rates cluster around $0.007 to $0.011 per SMS, with MMS costing roughly three to five times as much. For 10,000 single-segment US texts a month, that came to:

Platform	Approximate monthly SMS cost for 10,000 US texts
Klaviyo (toll-free sender)	$125
Postscript Starter	about $123 including average carrier fees
Omnisend	$85, plus its Pro plan
Brevo	$109 in prepaid credits

International texts cost more; Klaviyo’s calculator priced 1,000 SMS at $30 a month to Australia and $70 to the UK. Attentive quotes custom pricing. Our best SMS marketing platforms comparison shows the full rate cards and the sources.

Two hidden costs matter more than the rate card. First, segments: one emoji can turn a one-segment text into a three-segment text and triple the cost. Second, a second platform: if your SMS tool doesn’t do email, you’ll pay in syncing, reconciliation and attention.

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How to start SMS marketing: 8 steps

1. Pick a platform that shares data with your store and, ideally, your email. For most Klaviyo brands, that’s Klaviyo SMS. See our Klaviyo SMS marketing guide for setup.
2. Register your sending number before anything else. Toll-free verification and 10DLC registration take days to weeks; a US short code takes months. Nothing should go live on an unverified number.
3. Write your consent disclosure. Brand name, recurring automated marketing texts, not a condition of purchase, frequency, message and data rates, HELP and STOP, and links to your terms and privacy policy.
4. Add SMS opt-in to your pop-up and checkout. A two-step pop-up (email first, then phone) keeps your email capture intact while adding SMS.
5. Build three flows before your first campaign: welcome, abandoned cart or checkout, and back in stock. These trigger on intent and earn the most per message.
6. Send a welcome text that delivers the promise. If the pop-up offered a code, the first text contains the code. Set frequency expectations in the same message.
7. Add campaigns slowly. Start with two or three a month to engaged segments, then build toward four to six.
8. Measure what matters. Revenue per message against cost, unsubscribe rate per send, and list growth net of opt-outs.

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How to grow an SMS list for an online store

• Two-step pop-ups. Ask for email first, then phone on the second step, with the SMS incentive shown there. You keep the email even if they skip the phone.
• Checkout consent. An unticked SMS checkbox at checkout captures buyers at the highest-intent moment, and on most platforms consent syncs before the order is placed, which is what makes the abandoned checkout text possible.
• Keywords and QR codes. “Text GLOW to [number]” on packaging inserts, in-store signage and social posts. Keywords need a number that can receive replies, not a one-way sender ID.
• Email-to-SMS campaigns. Ask your engaged email subscribers to add SMS for early access. It’s the cheapest list growth you’ll ever run.
• Give a reason that isn’t only a discount. Early access, restock alerts and SMS-only drops build a list that stays subscribed after the code is used.

Never buy, rent or import a list without documented consent for every number on it.

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SMS vs email marketing: when to use each

SMS and email are complements, not competitors. The simplest rule: if it would feel urgent and useful at 11am on a Tuesday, it can be a text. Everything else is an email.

	SMS	Email
Best for	Time-sensitive, high-intent moments: carts, restocks, launches, deadlines	Storytelling, education, visuals, newsletters, longer offers
Length	160 characters per segment	Effectively unlimited
Cost	Per message, roughly $0.007 to $0.011 per US SMS	Included in a platform plan priced by list size
Consent bar	Highest: written consent in the US, plus carrier rules	Opt-in expected; rules vary by country
Frequency tolerance	Low: a few campaigns a month	Higher: several a week is common
Measurement	Clicks, orders, revenue per message, unsubscribes	Clicks, orders, revenue per recipient (opens are unreliable)

The strongest programs run both from one profile, with texts staggered after emails in the same flow rather than sent at the same moment. We cover the sequencing in Email + SMS Marketing in Klaviyo.

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SMS marketing examples

Three quick examples of texts that work, from our library of 32 SMS marketing examples:

Abandoned cart: [Brand]: Still thinking about the Linen Shirt in sage? Your cart’s saved: [link]

Back in stock: [Brand]: It’s back. The Wool Runner in size 9 is in stock again. You asked us to tell you first: [link]

Supplement replenishment: [Brand]: Your Magnesium Glycinate should be running low about now. Reorder in 2 taps so you don’t miss a night: [link]

Each one names the brand, uses something real about the customer, carries one link, and fits in a single segment.

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SMS marketing for supplement and health brands

Supplements are one of the best categories for SMS, because the product runs out on a predictable schedule. A replenishment text timed to days of supply at the recommended dose (“your 30-day tub should be running low”) is useful rather than intrusive, and a subscribe-and-save nudge after the second order turns a habit into recurring revenue.

Two cautions. Keep health and disease claims out of your texts; 160 characters doesn’t get a lighter standard than your product page. And time replenishment to the product, not to a flat “30 days after purchase” rule, or you’ll text people who still have half a tub. Our 10 email flows for supplement brands covers the replenishment logic for both channels.

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Choosing an SMS marketing platform

The short answer: choose the platform that shares a customer profile with your email, unless SMS is your main channel.

• Klaviyo SMS for brands already on Klaviyo, and most brands where email is the bigger channel.
• Postscript for Shopify brands where SMS drives a large share of revenue (Klaviyo vs Postscript).
• Attentive for enterprise programs with custom contracts (Klaviyo vs Attentive).
• Omnisend for a budget email and SMS tool on its Pro plan.

In Australia, Klaviyo supports SMS to Australian numbers from a branded sender ID or a local long code (MMS on long codes only), which covers ecommerce automation. Local bulk-SMS providers rank well for “SMS marketing Australia” searches and are fine for simple broadcasts, but most aren’t built around ecommerce events like abandoned carts. Whichever you use, register your sender ID.

The full comparison, with verified pricing, is in best SMS marketing platforms. If you’d rather hand the program over, see our ranking of the best SMS marketing agencies.

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Common SMS marketing mistakes

• Launching campaigns before flows. Flows earn more per message; build them first.
• Texting at the same moment as the email. Stagger the channels in the flow.
• Discounting in every text. It trains subscribers to wait and erodes margin.
• Emoji in everything. One emoji cuts the segment limit from 160 characters to 70.
• No frequency ceiling. Set a monthly campaign cap and hold it.
• Treating a shipping-updates number as marketing consent. It isn’t.
• Launching on an unverified sender. Registration comes first, especially before Black Friday.

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Want SMS that adds revenue without burning the list?

We build and run SMS marketing programs in Klaviyo for ecommerce brands: sender registration, compliant consent, SMS steps in the flows you already run, and reporting that sets SMS revenue against its cost. If you already send texts and want to know what they’re really earning, start with a free audit.