One of the things that sets Klaviyo apart from other email platforms is its integration ecosystem. Out of the box, Klaviyo connects with your e-commerce store and starts pulling in customer data. But the real power comes when you layer in the other tools your business already uses. Each integration feeds Klaviyo more information, which means smarter segmentation, more relevant automations, and more revenue from every email you send.
The integrations below are not nice-to-haves. They are the ones that consistently make the biggest difference for store owners who want to get the most out of Klaviyo. If you have any of these tools in your stack and they are not connected yet, this is your sign to fix that.
Your E-Commerce Platform
This one is the foundation, so it is worth saying clearly: if your Shopify, WooCommerce, or BigCommerce store is not connected to Klaviyo, nothing else in this list matters yet. The e-commerce integration is your foundation and it is what turns Klaviyo from a basic email tool into a behavioral marketing engine.
When your e-commerce store is connected, Klaviyo can see what every customer has purchased, what they have browsed, what they left in their cart, how often they order, and how much they have spent over their lifetime. That data is what powers your flows and segments. Without it, you are essentially sending blind.
If you have not connected your store yet, that is your first step. Everything else builds on top of it.
Your Reviews Platform
Customer reviews are some of the most persuasive content you can put in front of a prospective buyer, and your review platform is sitting on a goldmine of data that Klaviyo can use. Klaviyo has its own native review platform. It also integrates natively with Okendo, Yotpo, Stamped.io, Judge.me, and several other popular review tools.
Once connected, you can trigger automated emails that request a review at exactly the right moment after a purchase, pull star ratings and review snippets directly into your email templates, and segment customers based on whether they have left a review and what rating they gave. A customer who left a five-star review is a very different prospect for a referral ask or a loyalty program invite than someone who has never engaged with your review requests. This integration makes it possible to act on that difference automatically.
Your Loyalty and Rewards Program
If you are running a loyalty program through ethos, Okendo, LoyaltyLion, Smile.io, Yotpo Loyalty, or a similar platform, connecting it to Klaviyo lets you use points and rewards data in your email marketing in ways that genuinely move the needle.
With this integration enabled, you can send automated emails that notify customers when they are close to earning a reward, remind lapsed members of points they have not redeemed, and create segments based on loyalty tier or lifetime points earned. These emails perform extremely well because they are personal and they give customers a specific, tangible reason to come back and spend. A “you are 50 points away from a free gift” email is a very compelling message for the right customer at the right time.
Your Recurring Subscription App
If any of your products are available on a subscription or recurring order basis, connecting your subscription platform to Klaviyo is a must. Recharge, Bold Subscriptions, and Stay AI are among the most common integrations here.
This connection lets you trigger flows around subscription lifecycle events: welcome emails for new subscribers, renewal reminders before a charge, win-back sequences for customers who have canceled, and check-ins for customers who might be at risk of churning. Subscription customers are typically your highest-value customers, and yet many stores do very little email marketing specifically designed for them. This integration makes it easy to change that.
Your Help Desk
Connecting your customer service platform to Klaviyo might not be the first integration that comes to mind, but it is one that pays off in ways store owners do not always expect. Gorgias and Zendesk both integrate with Klaviyo.
With this connection, Klaviyo can see which customers have open support tickets, how many times someone has contacted your team, and whether a ticket was resolved. That context lets you suppress customers with open issues from receiving promotional campaigns at the wrong time, trigger a follow-up email after a support interaction is closed, and identify customers who have had repeated negative experiences and handle them differently in your flows. Small adjustments like these protect the customer relationship and reduce churn in ways that are easy to miss without the data.
Facebook and Instagram Ads
Klaviyo’s integration with Meta lets you sync your Klaviyo segments directly to Facebook and Instagram as custom audiences. This is one of the most underused integrations in the platform, and it can meaningfully improve your paid social performance.
The practical application is straightforward. Take your VIP customer segment, your lapsed customers, or your subscribers who have never purchased, and sync each one to Meta. You can then run ads specifically to those audiences or, just as importantly, exclude your existing customers from acquisition campaigns so you are not wasting budget on people who already know you. Using your email data to sharpen your paid social targeting consistently improves return on ad spend for stores that take the time to set it up.
Google Ads
The same logic applies to Google. Klaviyo’s Google Ads integration lets you push your segments into Google as customer match audiences, which means you can adjust your bidding, serve specific creatives, or exclude existing customers from certain campaigns across Search and YouTube.
For stores running any volume of paid search, syncing Klaviyo segments to Google is a quick win that does not require ongoing maintenance once it is set up. Your email data improves your ad targeting automatically as segments update in real time.
Postscript or Klaviyo SMS
If you are not already using SMS as part of your marketing mix, this is worth paying attention to. Klaviyo has its own native SMS product built directly into the platform, which means your email and SMS flows can share the same logic, the same data, and the same workflow builder without needing a separate tool.
For stores that want more flexibility or are already using a dedicated SMS platform, Postscript is the most popular integration. Either way, having SMS connected to your Klaviyo account means you can build cross-channel flows that reach customers on the channel most likely to get a response. An abandoned cart sequence that sends an email, then follows up with a text if the email goes unopened, consistently outperforms either channel alone.
Where to Start
If you are looking at this list and realizing you have a few of these tools in your stack but none of them connected to Klaviyo, start with the ones you are already paying for. Connecting an existing tool costs nothing and can usually be done in a matter of minutes through the Klaviyo integrations directory.
Each connection you make gives Klaviyo more data to work with, which means every email you send gets a little smarter. That compounding effect is a big part of what separates stores generating 15% of revenue from email from those generating 40%.
If you would like help identifying the right integrations for your specific stack or setting them up correctly, we are happy to take a look at what you have and point you in the right direction.
Continue reading: How to set up Klaviyo for your Shopify store and Klaviyo segmentation guide: How to stop emailing everyone the same thing.