SMS Marketing Guide
SMS has 98% open rates. But set it up wrong and you'll get fined.
Email gets you 30-40% of revenue when it's done right. Add SMS and you can push that to 40-50%. The numbers are compelling — 98% open rates, 10-15% click rates, and 90-second average response times. SMS cuts through the noise in a way email can't.
But here's the catch: SMS marketing has strict compliance rules. TCPA in the US, CASL in Canada, GDPR in Europe. Send a text to someone who didn't explicitly opt in and you're looking at fines up to $1,500 per message. Carriers will also block your number if your spam rate is too high.
Klaviyo makes SMS easy to manage alongside email — same platform, same customer profiles, same flows. But you need to set it up properly from the start. Here's how to do it without getting fined, blocked, or annoying your customers.
98%
SMS Open Rate
10-15%
SMS Click-Through Rate
90 sec
Avg. SMS Response Time
25%
Revenue Lift Adding SMS to Email
How to fix this — step by step
Enable SMS in Klaviyo and set up your sending number
In Klaviyo, go to Settings → SMS. Enable SMS and choose your sending number type — toll-free is the fastest to set up (active within 48 hours). Dedicated short codes take 8-12 weeks but have higher throughput for large lists. For most brands under 50K subscribers, toll-free is the right starting point. Klaviyo will walk you through carrier registration — complete this immediately because carriers can reject numbers that aren't properly registered.
Build a compliant opt-in system
SMS consent must be explicit and separate from email consent. You cannot add someone to your SMS list because they gave you their email. In Klaviyo, add an SMS consent checkbox to your popup forms, checkout flow, and any signup form. The opt-in language must include: your brand name, a description of the messages they'll receive, message frequency, "Msg & data rates may apply," and instructions to reply STOP to opt out. This isn't optional — it's required by law.
Set up your core SMS flows alongside email
The best SMS strategy uses SMS as a complement to email, not a replacement. In your existing Klaviyo flows, add SMS touchpoints: Welcome Series (SMS 1 hour after signup: "Welcome! Here's your code..."), Abandoned Cart (SMS 2 hours after abandonment — after the first email), and Post-Purchase (SMS shipping notification or delivery confirmation). Use conditional splits to only send SMS to subscribers who opted in. Never send the same message via both email and SMS at the same time — stagger them.
Limit campaign SMS to 4-6 per month maximum
SMS is intimate. It lands directly in someone's personal messages. Over-texting is the fastest way to get opt-outs and carrier complaints. For campaigns (non-automated), stick to 4-6 SMS per month maximum. Save SMS campaigns for high-impact moments: flash sales, product launches, BFCM, exclusive VIP offers. Every text should feel like it was worth sending. If it doesn't have a clear, timely reason, send it as an email instead.
Segment your SMS list just like email
Don't blast every SMS subscriber with every text. Segment by purchase history, engagement, and VIP status. Your VIP customers should get exclusive early access via SMS. New subscribers should get a softer touch. High-value cart abandoners should get a recovery text. Low-engagement SMS subscribers should get fewer messages to prevent opt-outs. Use Klaviyo's segment builder — it works identically for SMS and email.
Track SMS attribution and revenue separately
Klaviyo attributes revenue to SMS just like email. Check your SMS Revenue dashboard: flow SMS revenue, campaign SMS revenue, click rates, and opt-out rates. Your target: SMS should generate 15-25% of your total email+SMS channel revenue. If it's below 10%, your SMS strategy needs optimization. If opt-out rates are above 2% per campaign, you're texting too frequently or your content isn't relevant enough.
Want us to handle this?
Steps 1 through 4 get SMS live and generating revenue. Most brands can have SMS running within a week if they follow this guide.
But the real art is in the coordination — knowing when to use SMS vs. email, building flows that alternate channels intelligently, segmenting SMS differently than email, and optimizing send times for texts. We build integrated email+SMS programs for eCommerce brands on Klaviyo every day. If you want help setting it up or optimizing what you've already built, book a call.
Questions our best clients asked first
Want us to build your SMS strategy alongside email?
We'll audit your current email program, identify where SMS adds the most revenue, and build an integrated plan. Free strategy call — no commitment.
Pick a Time15 minutes. No pitch deck. Just your data and our honest take.
More guides
Klaviyo Setup Guide
Stores using Klaviyo properly drive 30-40% of total revenue from email. Here's how to set it up right.
Step-by-step guide to setting up Klaviyo on your Shopify store — from installation to your first automated flow. Written by a Klaviyo Gold Partner.
Learn moreEmail Automation Guide
Email flows generate 50-70% of your email revenue. Most stores have them broken or missing.
The 7 email flows every eCommerce store needs — with exact timing, content, and structure. From a Klaviyo Gold Partner managing 150+ brands.
Learn moreEmail Segmentation Guide
One of our clients went from $8K to $24K per month in email revenue. The only change? Segmentation.
Sending the same email to everyone? Segmented campaigns drive 3x more revenue per send. Here's the exact segmentation playbook for Klaviyo.
Learn moreList Building Guide
The average eCommerce store converts 1.5% of visitors into email subscribers. Here's how to hit 5-8%.
Growing your eCommerce email list from zero? Here's the exact playbook — popups, lead magnets, and signup strategies that actually convert visitors into subscribers.
Learn moreEmail Marketing Guide
Your open rates are dropping. And it's probably not your subject lines.
Email open rates below 25%? The fix isn't a better subject line — it's your sender reputation. Here's the exact playbook from a Klaviyo Gold Partner.
Learn moreEmail Performance Guide
People are opening your emails but not clicking. Why?
Getting opens but no clicks? Your email layout is the problem. Here's the eCommerce email design playbook that consistently drives 3-5% click rates.
Learn moreNeed help with this?
Book a free call