Klaviyo vs Attentive: SMS for Ecommerce Compared
Attentive is the SMS-first specialist. Klaviyo is the unified email + SMS platform. Where each wins, what you give up either way, and the honest recommendation.
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Attentive is the leading SMS-first marketing platform in ecommerce. Klaviyo started as email and added SMS later, but has invested heavily and now offers SMS as a unified product alongside email. The question for brands isn’t which platform is “better”, they’re built for different things, and which is right depends on how much you value SMS specialism vs. unified email/SMS architecture.
This is an honest comparison: where Attentive’s SMS-first design choices win, where Klaviyo’s unified approach wins, and what changes when brands consolidate from a two-platform stack (Klaviyo email + Attentive SMS) onto Klaviyo for both.
Attentive Is SMS-First; Klaviyo Is Email-First With Strong SMS
The core architectural difference. Attentive was built for SMS from day one and has the deepest SMS-specific feature set in ecommerce: live agent capabilities, advanced opt-in flows including overlay campaigns and two-tap mobile journeys, conversational commerce, MMS optimisation, and a copy team that specialises in SMS. The SMS depth genuinely shows.
Klaviyo’s SMS started as a feature inside the email platform and has grown into a competent product, but it’s still architected as “email plus SMS” rather than “SMS native.” For most ecommerce brands, Klaviyo SMS is good enough. For brands where SMS is a primary channel (>40% of retention revenue), Attentive’s specialism may be worth the two-platform overhead.
Pricing: Different Models Entirely
Attentive prices on revenue performance. The base pricing is roughly 20-25% of the SMS-attributed revenue, with floors and minimums that vary by account size. For brands generating significant SMS revenue, Attentive can be expensive in absolute terms but predictable as a percentage of attributable revenue.
Klaviyo SMS prices on volume sent, similar to email pricing. Tier-based on monthly active SMS profiles, with separate SMS message costs per send. For most brands, Klaviyo SMS is materially cheaper than Attentive in dollar terms, particularly at scale.
The pricing comparison gets complicated because Attentive includes services (creative, strategy, opt-in optimisation) inside the platform fee that Klaviyo does not. For brands that would otherwise hire an SMS-specialist agency or in-house SMS lead, Attentive’s bundled pricing may be competitive once you factor in services.
For brands managing SMS in-house or with a Klaviyo-specialist agency: Klaviyo SMS is significantly cheaper.
Where Attentive Wins
SMS-specialist features. Two-tap opt-in flows, overlay campaigns with mobile-optimised UX, MMS rendering optimisation, and conversational AI for inbound replies. All of these exist in Klaviyo to some degree but are deeper and more polished in Attentive.
Bundled creative and strategy services. Attentive’s pricing includes campaign creative, copy, and strategic input from their internal team. For brands without internal SMS expertise or a Klaviyo agency, that bundled service is real value.
Opt-in conversion rates. Attentive’s opt-in flows are genuinely industry-leading. Pop-up overlays, two-tap mobile signups, and SMS-specific lead magnets typically convert at 8-15% of mobile traffic, materially better than Klaviyo’s standard pop-up conversion in our testing.
Operator depth in SMS. Attentive’s customer success teams, training materials, and benchmarking data are SMS-specific in a way Klaviyo’s are not. For brands learning SMS marketing for the first time, the resource quality matters.
Where Klaviyo Wins
Unified email + SMS profile. A subscriber on Klaviyo who opts into both email and SMS has a single profile with full cross-channel engagement history. Flows can fire emails or SMS based on the same trigger logic, with smart channel routing (e.g., “send SMS if the customer opens emails on mobile, send email otherwise”). With Klaviyo email + Attentive SMS as separate platforms, you maintain two profile databases that need syncing, two opt-in records, two segmentation systems, and two attribution models that may or may not agree.
Cost. Materially cheaper at any meaningful scale. For brands at $5M+ revenue, the platform cost difference between Klaviyo SMS and Attentive can run $20-100K annually.
Single-platform reporting. Klaviyo reports unified revenue across email and SMS, with cross-channel attribution and segment-level performance. Attentive reports SMS performance; cross-channel attribution requires manual reconciliation or third-party tooling.
Ecosystem integration. Klaviyo’s ecosystem (Shopify, BigCommerce, Postscript-alternatives, review tools, loyalty platforms) integrates with both email and SMS through one connection. Attentive integrations cover SMS but not email; you maintain duplicate connections.
Flow architecture. Klaviyo’s email flows can fire SMS as a step within the same flow (“if not opened email after 24h, send SMS”). Attentive flows are SMS-only; cross-channel orchestration requires triggering between two platforms.
Pricing Comparison at Scale
For an ecommerce brand at $10M annual revenue with email + SMS contributing combined 30% of revenue ($3M), with SMS contributing roughly $1M of that:
Two-platform stack (Klaviyo email + Attentive SMS):
- Klaviyo email: ~$700-1,000/month for the email side
- Attentive SMS: ~$15-20K/month at 20% of $1M attributed SMS revenue
- Combined: ~$190-250K annually
Single-platform stack (Klaviyo email + SMS):
- Klaviyo email + SMS: ~$1,500-2,500/month combined
- SMS message costs: ~$2-4K/month based on send volume
- Combined: ~$45-80K annually
The platform cost gap is roughly 3-4x, with Attentive bundling services that the Klaviyo-side requires you to handle separately. For brands with internal capability or a Klaviyo agency, the $100-150K annual difference is meaningful.
When to Choose Attentive
Three scenarios where Attentive is the right choice:
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SMS is your dominant retention channel. Brands where SMS contributes >40% of retention revenue benefit from Attentive’s specialism. The depth of features, the opt-in conversion advantage, and the SMS-specific operator support all compound into materially better SMS performance.
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You have no internal SMS or email capability and want bundled services. Attentive’s pricing includes creative, copy, and strategic support. For brands not running an in-house team or agency relationship, the bundled service is competitive.
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You’re already running Klaviyo well for email and don’t want to disrupt it. If your email program is healthy on Klaviyo and you’re adding SMS as a separate initiative, Attentive’s SMS specialism may justify the two-platform stack despite the integration overhead.
When to Choose Klaviyo (Both)
Most ecommerce brands at $1-30M revenue should run unified Klaviyo email + SMS:
- Material cost savings (typically $50-150K annually at scale)
- Unified profile, segmentation, and attribution
- Cross-channel flow orchestration
- Single-platform operational overhead
- Klaviyo SMS is good enough for most ecommerce SMS use cases
The exception is the SMS-dominant case (point 1 above), where Attentive’s specialism may be worth the cost and complexity overhead.
Migration: Attentive to Klaviyo SMS
Brands consolidating from Attentive to Klaviyo SMS face a few migration constraints:
- SMS opt-in records must transfer with TCPA-compliant double-opt-in preserved
- Sender numbers / shortcodes need migration or replacement
- Flow logic rebuilt in Klaviyo (Attentive workflows don’t import directly)
- Templates and copy migrate as content but template structure rebuilds
A typical Attentive-to-Klaviyo SMS migration runs 2-4 weeks for most brands. We handle these as part of broader Klaviyo engagements; happy to scope as a standalone project if that’s the priority.
Practical Recommendation
For most ecommerce brands at $1-30M revenue: run Klaviyo for both email and SMS. The cost savings, unified profile, and cross-channel orchestration outweigh Attentive’s SMS-specific depth advantages.
For SMS-dominant brands at scale: Attentive may be worth it. Particularly for brands where SMS is the primary retention channel and the additional cost is justified by the performance advantage.
For brands evaluating right now: the question we’d ask first is “what percentage of our retention revenue comes from SMS today, and how much do we plan to invest in SMS over the next 12 months?” Below 30% retention contribution from SMS, the unified Klaviyo answer is almost always right. Above 50% with active investment, Attentive’s case strengthens.
If you’d like to talk through which fits your specific business, book a free audit. We work primarily in Klaviyo but have honest opinions on when Attentive is the right answer.