Four Integrations That Klaviyo Agencies Rely On

There are 363 Klaviyo integrations in the marketplace. We’ve chosen to share the 4 integrations that our Klaviyo agency relies on to improve Klaviyo’s capabilities and generate the best results for our clients.

These four are the ones we install in our client accounts:

• Littledata gets your cart and browse events onto the right profile, so your flows stop firing at half strength.
• Recharge puts subscription state somewhere a flow can read it.
• Yotpo turns a review score and a loyalty tier into something you can segment on.
• Track by Loop, formerly Wonderment, fires your post-purchase flows the moment the parcel lands.

We're a Klaviyo Master Platinum Partner and we've built retention systems for 140+ DTC brands. We’ve tested almost every integration in the Klaviyo marketplace and found these four to be the best ones. 

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Littledata closes the identity gap that hides your best subscribers

Someone subscribes through your popup, hands over their email, and starts browsing. Klaviyo can email them, but it can't see what they add to cart, so your abandoned cart flow never fires for the subscriber you just paid to acquire.

Your app embed is on and klaviyo.js is firing, so nothing is misconfigured. Those flows fire on what a shopper does on your site, and Shopify only reports that behavior for people it already knows: logged-in customers, or shoppers who entered an email at checkout.

A popup subscriber is neither. Littledata sends those events to Klaviyo and attaches them to the right profile. Now your newest subscribers reach the abandoned cart and browse abandonment flows built to win them back.

Why your added-to-cart count is lower than your real one

This isn't our theory. Littledata's founder and CEO, Edward Upton, puts the scale of it plainly: client-side tracking can miss up to 30% of conversions.

One operator, posting as u/iwearshmedium, measured a week of add-to-cart events on their own store in a thread on third-party apps.

"One of our best selling points against Klaviyo was identity resolution that far exceeded Klaviyo out of the box... Last 7 days for add to cart metric. Klaviyo event: 1,339. Sonar event: 1,867. Restore.ai event: 2,778."

Read the gap, not the brand names. Klaviyo caught 1,339 add-to-cart events; a server-side tool caught 2,778. Nearly half the real activity never reached Klaviyo's flows.

It's one store's numbers, so treat it as a signal rather than proof. And Restore.ai, the tool they rated highest, isn't the one we deploy. We're citing the size of the gap, not their stack.

Littledata is the server-side tracking we install against it. Its PersistentID identifies shoppers who never typed an email at checkout, and its Added to Cart event carries the whole basket, so your recovery email can name the actual cart.

What multi-email profiles changes, and what it leaves open

Klaviyo closed part of that gap itself on 29 June with multi-email profiles, though not the part Littledata is doing for you: one view of a customer across up to five email addresses.

That's genuinely useful. The person who checks out as a guest on a work address and subscribes on a personal one finally stops being two people.

But it merges the identities Klaviyo already holds, not the ones Klaviyo never saw in the first place. No cart event means no second identity to merge, so both jobs still need doing.

Subscription state never reaches Klaviyo without Recharge

A subscriber pauses, then cancels a month later. You'd have wanted to step in at the pause, but Klaviyo never saw it, because it doesn't know they're a subscriber at all.

Subscriptions run on Recharge, the app that handles recurring billing on Shopify. Shopify tells Klaviyo about one-off orders. The renewal dates, pauses and cancellations all live in Recharge, out of Klaviyo's reach.

Connect the two and Klaviyo finally sees the subscription. Now your flows can trigger on a renewal, a pause or a cancel.

Segments a subscription renewal date makes possible

Take that renewal date. It's a countdown, so once Klaviyo can read it you get to send before the charge instead of apologizing after it.

You can also catch the pause that comes before the cancel, which is the useful one. Recharge fires a paused-subscription event into Klaviyo, and almost nobody churns without warning first.

And you stop doing the thing every subscription brand does by accident. Emailing a welcome discount to someone who already pays you monthly.

Dense Hair Experts had a version of this timing problem. We rebuilt their sequence around when their customers genuinely decide, which for them meant men in their thirties who'd already watched a treatment fail once. Returning-customer revenue rose 59% in under 90 days.

Connect Yotpo and a five-star review becomes a segment

A customer leaves a five-star review and joins your loyalty program. Both tell you something worth acting on, but neither reaches Klaviyo on its own.

Those two signals live in Yotpo. It runs your reviews and loyalty, and connecting it to Klaviyo turns each into something you can segment on.

So reviewers become a segment, and so do the people who left three stars. That second group is a very different audience, and they shouldn't be getting the same campaign as the people who just told the world they love you.

Loyalty tier is the other half of it. A points balance separates a generic promo from a message telling someone they're 200 points short of the next tier. Same send, different open rate.

This is where it compounds. KittySpout came to us having scaled from 10,000 to 500,000+ customers on a program that had never kept up. We built them a rewards structure tied to subscription milestones and rebuilt the post-purchase flows around it, which took them to a 146% increase in returning-customer revenue.

Delivery events beat order events for post-purchase timing

A post-purchase flow usually fires on the order, which is why your review request lands while the parcel is still rattling around in the back of a van.

That timing comes from Track by Loop. It watches where a parcel is in transit and turns each stage into a delivery event in Klaviyo: out for delivery, delivered, or stalled.

So the review request waits for the thing to turn up, and replenishment counts from the day it landed rather than the day they paid.

Stalled shipments are the sleeper here. A parcel stuck for four days is the highest-intent support ticket you'll never receive, because customers rarely complain about it — they just stop coming back.

An email that gets there first turns that silence into a save.

One naming note, since it affects the list further down. Loop acquired Wonderment and rebranded it, so the tracking tool here and the returns app below share a vendor. They're still two separate products, bought and installed separately.

Bonus integrations that depend on how your store operates

Stacks grow. Survey data shows that 62.9% of marketers who replaced a martech tool ended up with more tools than they started with, and only 22.6% shrank their stack at all.

So adding is easy. Adding well needs a reason.

These three have one, and none of them depends on the four above. They attach to Klaviyo profiles by email address and work perfectly well on a bare account. Install them in any order, or not at all.

Gorgias pauses Klaviyo sends to customers with an open ticket

Support tickets are the case here, and Gorgias can pause Klaviyo campaigns and flows for anyone with an open ticket. A customer mid-complaint about a broken order shouldn't receive a cheerful discount. Worth it if your helpdesk carries real volume.

Loop Returns turns a return or exchange into a Klaviyo flow trigger

Then there's Loop Returns, which pushes its whole return event set into Klaviyo — from return created through to instant exchange not received.

So returns stop being an ops problem in another tab. Worth it if returns are a real cost line.

Octane AI puts quiz answers onto the Klaviyo profile

Quiz answers land as custom properties on the profile, so Octane AI hands you zero-party data. What the customer said they want, rather than what you inferred. Worth it if you sell something that needs a recommendation.

Where a Klaviyo partner fits into this

Any agency can install four integrations. Knowing whether the ones you already have are writing anything usable is the hard part. That's the genuinely difficult bit, because a cart event that fires half the time looks identical to one that fires every time, right up until you compare it against reality.

So that's the job a free Klaviyo audit does. We go through your account the way we'd go through our own and come back with what's connected and what silently isn't.

That means the flows firing on the wrong trigger, and the places revenue leaks through the gaps between tools. You keep the findings whether or not you work with us.

We've now done this across 140+ DTC brands and the pattern repeats. The stack usually isn't too small. It's pointed the wrong way, connected but firing on the wrong triggers.

Find out what your Klaviyo integrations are really writing. Get your free Klaviyo audit.

Klaviyo integrations FAQ

How many integrations does Klaviyo have?

363 apps sat in the marketplace when we counted in July 2026, spread across 28 categories. Klaviyo's own marketing says 350+, so the catalog roughly matches the claim. The number of Klaviyo integrations that matter to your store is far smaller.

Are Klaviyo integrations free to connect?

Connecting them is free, but the apps themselves usually aren't, and that's the real cost of a long list. Every tool is a monthly line item plus the attention needed to keep it configured.

Which Klaviyo integration should I add first?

Whichever one fixes identification, before anything that adds new data. Enriching profiles your events can't find is wasted money.

Does Klaviyo have an API for custom integrations?

It does, and building a custom one is perfectly normal when a tool isn't in the marketplace. Klaviyo's own setup documentation covers the standard ecommerce connection first, which is where most stores should start.

Do I need a separate CRM integration if I use Klaviyo?

Usually not, though the CRM category is a bigger one than you'd expect. Twenty of the 363 sit there, and most are built for sales teams working a pipeline rather than stores selling products.

So connecting one tends to duplicate the customer record instead of adding to it. Klaviyo already holds that record for most DTC brands, which is why we generally run it as the CRM and integrate around it.

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