If you run an ecommerce store on Shopify, you have probably asked yourself whether to push your marketing budget into email or SMS. Both live inside Klaviyo. Both can drive revenue. But they are not interchangeable, and the wrong channel for the wrong campaign is money left on the table.
Klaviyo's 2026 Omnchannel Benchmark Report, drawing from over 183,000 brands, shows that the brands doing this well treat email and SMS as separate tools for separate jobs. This post breaks down what each channel does best, the numbers behind them, and how to combine them without doubling your workload.
Why the channel decision matters more than the tool
Klaviyo is the platform, but email and SMS have fundamentally different economics and behaviour. Email is a high-volume, low-cost channel that builds relationships over time. SMS is immediate, personal, and expensive but it converts at rates email rarely touches.
According to Klaviyo's email benchmarks, email flows deliver over three times higher click rates than campaigns (5.58 per cent versus 1.69 per cent) and 13 times higher placed order rates. The difference is relevance: flows are triggered by behaviour, campaigns are sent to a list. That gap tells you something about how your customers respond to timing.
On the SMS side, industry data puts SMS conversion rates between 21 and 30 per cent, roughly double typical email benchmarks. Open rates hover around 95 per cent, compared to 31 to 45 per cent for email. But SMS costs more per message and carries a higher unsubscribe risk if you overuse it.
Option A: Klaviyo Email Sequences
Email is the workhorse of ecommerce marketing. Klaviyo's strength is in its segmentation and flow builder, letting you trigger emails based on what customers do rather than sending the same message to everyone.
Key benchmarks for Klaviyo email in 2026:
| Metric | Campaigns | Flows (automated) |
|---|---|---|
| Open rate | 31.0% | 45.1% |
| Click rate | 1.69% | 5.58% |
| Revenue per recipient | $0.32 | $0.89 |
| Order rate | 0.3% | 3.9% |
Welcome flows see open rates of 40 to 60 per cent with conversion rates of 8 to 12 per cent, according to the Darkroom agency analysis of Klaviyo data. For brands doing AUD 5 million or more in revenue, email typically drives 50 to 60 per cent of total email-attributed revenue through flows alone.
Where email shines is depth. You can tell a story, explain a product, share a customer review, and build trust over a sequence of messages. A welcome series can be five emails over two weeks. An abandoned cart flow can send three reminders with increasing urgency. Email gives you the space to do that without feeling intrusive.
We covered how to build AI email nurture workflows with Claude and HubSpot in a previous post, and the same principles apply to Klaviyo flows. The tool changes but the strategy is the same: send the right message at the right time, informed by behaviour.
Option B: Klaviyo SMS Marketing
SMS is a different beast. The 95 per cent open rate is not a sign of better content, it is a sign of a different medium. People open texts. They read them in seconds. And they act on them or they do not.
Klaviyo's SMS marketing benchmarks show click rates vary significantly by industry, with top-performing segments seeing click rates above 10 per cent and conversion rates between 21 and 30 per cent. The revenue per recipient depends heavily on list quality and message frequency.
The catch is cost and compliance. SMS costs more per message than email, and Australian law requires clear opt-in, opt-out, and sender identification. Klaviyo integrates with Twilio to handle provisioning and compliance, but you need to factor those costs into your campaign budgets.
SMS works best for:
- Cart abandonment reminders with a time-limited discount
- Flash sale announcements
- Order updates and shipping notifications
- Exclusive VIP offers
- Event reminders and appointment confirmations
It works poorly for educational content, long product descriptions, or anything that requires a link to be useful. If your SMS needs a click to make sense, you are using the wrong channel.
When to use each channel
The decision comes down to intent and timing.
Use email when the goal is education, relationship building, or nurturing over time. Welcome sequences, post-purchase follow-ups, newsletter content, and product education all belong in email. You have the space to build a case and the customer is in a reading mindset.
Use SMS when the goal is immediate action. A cart sitting for three hours, a flash sale closing tonight, or a low-stock alert all benefit from SMS because the customer sees it now. SMS is the channel that converts intent into revenue in minutes, not days.
The cost difference matters. Email costs near zero per send. SMS costs cents per message. If you send a weekly newsletter via SMS, you will burn through your marketing budget and your subscriber list simultaneously. If you never send an SMS, you are ignoring the customers who want to hear from you on their phone.
The hybrid approach: both channels together
The best Klaviyo setups use both channels in the same flow. A typical hybrid abandoned cart flow looks like this:
- Email 1 (1 hour): Reminder of what was left behind, with product image and link
- SMS (3 hours): Short text with a discount code if they order in the next 24 hours
- Email 2 (24 hours): Social proof, reviews, or restock fear
- SMS (48 hours): Final offer, expiring soon
Klaviyo makes this straightforward because both channels live in the same flow builder. You set the trigger once, add conditional splits based on whether the customer has opted in to SMS, and configure each message in its own channel.
This approach gives you the reach of email with the urgency of SMS, and it avoids the biggest mistake of each channel: email that is too slow, and SMS that is too frequent.
For a deeper look at cart recovery specifically, see our guide on building a cart abandonment recovery agent with Claude and n8n.
What we recommend and why
Start with email. Build a solid flow-based email programme first, because email gives you the highest ROI for the lowest cost. Focus on welcome flows, abandoned cart recovery, and post-purchase sequences. Measure flow revenue as a percentage of total email revenue and aim for 50 to 60 per cent.
Once your email flows are running well, add SMS for the specific moments where immediacy matters. Cart reminders that have not converted after a few hours, flash sales, and VIP offers work well. Set up each SMS message as a conditional branch inside an existing email flow, not as a standalone campaign.
And keep your lists segmented. Klaviyo's power is in behavioural segmentation. A customer who buys monthly should receive different messages, on both channels, than someone who visited once and left. The channel choice matters less than the relevance of the message, but getting both right compounds the effect.
Frequently asked questions
Is Klaviyo SMS more effective than email for ecommerce?
SMS typically sees higher open rates (around 95 per cent) and conversion rates, while email generates more revenue per send at a lower cost. The best approach uses both channels for different job types.
Can I use both Klaviyo SMS and email together?
Yes. Klaviyo supports hybrid flows that use both channels. The most effective strategy uses email for primary nurture and SMS for time-sensitive offers.
What is a good Klaviyo SMS conversion rate?
Klaviyo SMS conversion rates typically range from 21 to 30 per cent for well-segmented audiences, roughly double typical email benchmarks.
When should I use email instead of SMS?
Use email for welcome sequences, educational content, post-purchase follow-ups, and newsletters. Use SMS for flash sales, cart reminders, and urgent offers.
How do I set up Klaviyo SMS?
You need a Klaviyo account with SMS enabled, a dedicated phone number, and opt-in compliance. Klaviyo handles provisioning through its Twilio integration.