Sendlane vs Klaviyo for Shopify Brands: What the White-Glove Migration Tells You

Sendlane and Klaviyo are both ecommerce email and SMS platforms built around flows a marketer designs. Klaviyo prices per contact stored and has the deeper Shopify data. Sendlane prices per send with unlimited contacts and offers white-glove migration. Both bill for a builder someone operates. The newer option is autonomous decisioning, which has no flows to migrate.

We build the autonomous option, so read this as informed but interested. The comparison below is fair to both incumbents, including where each one beats us on its own terms. The reframe at the end is ours.

Where Sendlane wins

• You pay for sends, not for storage. Contacts are unlimited and the bill tracks email volume, so a large list with a long dormant tail costs nothing to keep. For brands whose Klaviyo invoice grew with contacts they never mail, this is the whole argument.
• Migration and onboarding are done with you. On its Enterprise tiers Sendlane’s team exports and imports your contacts, connects your integrations and runs custom onboarding; Professional gets assisted onboarding. For a lean team that dreads the switch, that is a real feature.
• Email, SMS, forms and reviews in one product. Signup forms and product reviews live inside the platform, which trims the app stack for a smaller brand.
• Support from people. Live specialists on chat during business hours and hands-on onboarding. Sendlane sells on service, and for many operators that beats a knowledge base.

Where Klaviyo wins

• Shopify-native depth. Orders, browse events, checkouts and the catalog sync without middleware, and segments act on that behavior directly.
• The flow library. Every lifecycle moment has a template that already understands a store.
• Revenue reporting. Dollars attributed per flow and per campaign, the number a DTC operator is actually asked about.
• Ecosystem. Agencies, apps and integrations built specifically around Klaviyo on Shopify. If an agency runs your email, they almost certainly know Klaviyo better.

The honest read on each. Sendlane’s ecommerce depth is a step behind: the data model, the segmentation and the reporting are strong but not where Klaviyo is, and the ecosystem is smaller. Klaviyo’s weakness is the meter: the bill tracks contacts retained, so the list you are afraid to prune is a recurring cost. Neither is a defect. Each is the shape of the product. We wrote up the Klaviyo side in more detail in our Klaviyo pricing breakdown.

What the white-glove migration tells you

This is the part worth sitting with. Sendlane’s most persuasive offer is that its team will move you over: contacts, integrations, onboarding. Read that offer carefully, because it is an admission about the whole category. A migration needs a team because the work is large. The contacts and integrations move, and then every branch, every wait step, every segment definition and every template has to be recreated in a new builder, with their onboarding people or on your own. The work is large enough that a vendor has made helping with it a selling point.

That is the real switching cost in ecommerce email, and it is why so many brands stay on a platform they no longer like. It is not the data, which exports in an afternoon, and it is not the list, which moves in an hour. It is the months of accumulated flow logic that only exists inside one vendor’s builder. Sendlane has correctly identified that cost and offered to share it. What the offer cannot change is that after the migration, the flows are the same flows in a new builder, maintained by the same person, plateauing on the same schedule.

So a like-for-like migration moves the work. It does not remove it. A brand that switches over the contact meter gets a better bill and the same job. That is a fine trade if the bill was the problem. It is no trade at all if the problem was flat revenue from flows that stopped improving a year ago. When results plateau, the answer in both builders is more flows, which is more of the work the migration just moved.

The alternative: nothing to migrate

Relvino has no flow builder, so there is nothing to rebuild. It runs an autonomous loop, Observe → Decide → Act: it watches live shopper signals from the store, decides the offer, timing and channel for that one shopper in about 80 milliseconds, and executes across email, SMS and on-site. You set guardrails once, including margin floors, send frequency, quiet hours and brand voice, and 100% of flows run without a human in the loop.

The migration is the tell in reverse. The technical cutover takes about 30 minutes, because the only things that move are the sending domain, the Shopify app and the historical data, and nothing is recreated. Gearit had 2× flow revenue delivered in 12 days. The engine is a Large Retail Model trained on 7M+ data points across 10K+ retailers and 1.78M shoppers, so it starts with priors about what works in a category instead of learning a store from zero. Brands leaving Klaviyo see 3× ROI in 30 days, 4× revenue uplift year over year and 80% less spam, on a bill that runs 3–7× cheaper than Klaviyo (see pricing). Joshua Rockoff, CMO of Omni Retail Enterprises, an early Klaviyo investor and a Relvino advisor, migrated four of his own brands: “Relvino is better than Klaviyo. Next gen is Relvino.”

Sendlane vs Klaviyo vs Relvino at a glance

• Built for · Sendlane: Shopify and ecommerce brands that want service · Klaviyo: Shopify ecommerce · Relvino: Shopify ecommerce, run autonomously
• Pricing meter · Sendlane: Sends, unlimited contacts · Klaviyo: Contacts stored · Relvino: Weighted to outcomes, 3–7× cheaper than Klaviyo
• Switching cost · Sendlane: Contacts and integrations moved by their team; flows rebuilt in their builder · Klaviyo: Flows rebuilt by you or your agency · Relvino: Nothing to rebuild; 30-minute migration
• Core model · Sendlane: Hand-built automations · Klaviyo: Hand-built flows · Relvino: Autonomous decisions
• Ecommerce data depth · Sendlane: Strong, a step behind Klaviyo · Klaviyo: Deep and Shopify-native · Relvino: Deep, plus cross-retailer priors
• Personalization · Sendlane: Segment-level · Klaviyo: Segment-level · Relvino: 1:1 per shopper in ~80ms
• Who runs it · Sendlane: A marketer in an automation builder · Klaviyo: A marketer in a flow builder · Relvino: Guardrails you set once

So which should you choose?

A decision rule that holds up: name the problem before you pick the meter. If the problem is the Klaviyo bill, and the list is large with a long tail you never mail, Sendlane’s send-based pricing and white-glove onboarding solve exactly that, and the service is real. If the problem is depth, meaning your revenue depends on catalog logic, fine-grained segments and an agency that lives in Klaviyo, stay, and prune the list instead. Our Klaviyo vs Omnisend comparison covers the other ecommerce-native challenger, and Klaviyo vs Flodesk the design-first one.

There is a third case, and it is the common one at $20–100M GMV. The problem is neither the bill nor the depth. It is that the flows are built, the team is lean, and revenue from the stack has been flat for three quarters. Moving those flows to a new builder, however painlessly, does not touch that. That is what autonomous decisioning is for. Run a 14-day pilot alongside what you already have and compare revenue directly. The wider field is mapped in Klaviyo competitors, and the practical cancellation steps are in how to cancel Klaviyo.

Frequently asked questions

Who competes with Klaviyo?

The useful way to sort Klaviyo’s competitors is by what they charge for. Billed per contact stored: Klaviyo, Mailchimp, Omnisend and Constant Contact. Billed per send: Sendlane, Brevo and most SMTP-first providers, with SMS-first tools such as Attentive and Postscript billing per message. Every one of those meters prices activity, and every one of those products is a builder a person operates. Relvino competes on a different axis, replacing the flow stack with autonomous decisioning rather than offering a cheaper way to build the same flows.

Is email marketing still worth it in 2026?

Yes, and for a Shopify brand it is often the highest-return channel it owns, because it reaches people who already chose to hear from the store. What has stopped being worth it is the way most brands run it: hand-built flows that send the same sequence to everyone and plateau once the initial build is done. The channel is fine. The return depends on whether each message is a decision about a shopper or a schedule applied to a list.

What are the weaknesses of Klaviyo?

Set against Sendlane, three stand out. The contact meter: Klaviyo bills for people on the list whether or not they are mailed, so unpruned growth is a standing cost. Service: Klaviyo’s paid plans get email and chat support, but a dedicated onboarding specialist or success manager is reserved for its highest tiers, where Sendlane leads with hands-on onboarding. And switching cost: because the flow logic lives in Klaviyo’s builder, leaving means rebuilding. Its deeper weakness, shared with Sendlane, is that it sells a builder, so flows improve only when somebody improves them.

Is Flodesk better than Klaviyo?

For a creator, a coach or a small brand that sells mainly on design and a newsletter, often yes: Flodesk is simpler, prettier and priced flat. For a Shopify brand whose revenue depends on cart, browse and repeat-purchase behavior, no: Klaviyo’s store data and flow depth are in a different class, and Flodesk’s ecommerce features are thin. Sendlane sits closer to Klaviyo than to Flodesk on that spectrum. We compare the two directly in Klaviyo vs Flodesk.

How long does it take to migrate from Klaviyo to Relvino?

About 30 minutes for the cutover, because nothing is rebuilt: the sending domain authenticates, the Shopify app installs, and historical data ingests on its own. That is the whole difference from a Sendlane migration, where the flows still have to be recreated. Revenue runs on a different clock: run a 14-day pilot with Klaviyo paused, not cancelled, and compare the two before deciding.