Klaviyo’s official WooCommerce plugin tracks exactly 8 events. If your store runs subscriptions, memberships, wishlists, or custom forms, you’re missing the data that powers Klaviyo’s most powerful features—flows triggered by customer actions the plugin doesn’t recognize.

Beyond the 8 Standard Events: What Your Flows Are Missing

The Track API changes this. It accepts unlimited custom event types with any properties you want to include, sent server-side so ad blockers can’t interfere. No waiting for Klaviyo to add support. No plugin limitations.

What the Official Plugin Actually Tracks

Klaviyo’s WooCommerce integration supports these events and only these events:

• Active on Site — Customer browsing (requires JavaScript)
• Viewed Product — Product page views (requires JavaScript)
• Added to Cart — Cart additions (requires JavaScript)
• Started Checkout — Checkout page loads
• Placed Order — Purchase completed
• Fulfilled Order — Order marked shipped
• Cancelled Order — Order cancelled
• Refunded Order — Order refunded

That’s it. No subscription renewals. No membership upgrades. No wishlist additions. No custom form submissions. No back-in-stock notifications.

If you want to trigger a flow when a subscription renews, segment customers who’ve added items to wishlists, or send different emails based on membership tier changes—the official plugin can’t help you.

The Track API: Unlimited Custom Events

The Klaviyo Track API is a server-side endpoint that accepts any event type with any properties. You send an HTTP POST request, and Klaviyo records the event against the customer profile.

Track API accepts unlimited custom event types with any properties (Klaviyo Developer Docs). You define the event name, the customer identifier, and whatever properties make sense for your use case.

Example events you could send:

• Subscription Renewed — with subscription ID, plan name, renewal amount, next renewal date
• Wishlist Item Added — with product ID, product name, price, category
• Membership Upgraded — with old tier, new tier, upgrade value
• Back In Stock Request — with product ID, customer email, request date
• Contact Form Submitted — with form name, submission data, lead score

You may be interested in: Why Klaviyo Shows Fewer Orders Than WooCommerce: The Integration Gaps Nobody Explains

Why Server-Side Matters

The first four events in Klaviyo’s standard integration—Active on Site, Viewed Product, Added to Cart, and Started Checkout—all require JavaScript running in the customer’s browser. 31.5% of global users run ad blockers (Statista, 2024). Brave browser blocks Klaviyo by default. Safari limits tracking capabilities.

When you send events via the Track API, they come from your server. The customer’s browser settings, ad blockers, and privacy extensions don’t matter. The event reaches Klaviyo regardless.

For purchase events, Klaviyo’s plugin does have a server-side fallback through webhooks. But for custom events? You’re entirely dependent on the Track API if you want reliable delivery.

WooCommerce Hooks: Your Custom Event Triggers

WooCommerce fires hooks for virtually every action that happens on your store. These hooks are the trigger points for custom events. When the hook fires, you capture the relevant data and send it to Klaviyo’s Track API.

Common hooks for custom events:

Use Case	WooCommerce Hook	Custom Event Name
Subscription renewal	woocommerce_subscription_renewal_payment_complete	Subscription Renewed
Membership purchased	wc_memberships_user_membership_created	Membership Created
Membership upgraded	wc_memberships_user_membership_status_changed	Membership Status Changed
Wishlist item added	yith_wcwl_added_to_wishlist (YITH)	Wishlist Item Added
Review submitted	comment_post (filtered for reviews)	Review Submitted

The hook fires, your code captures the event data, formats it for Klaviyo’s API, and sends it server-side. No browser involvement.

Flows That Require Custom Events

Once custom events reach Klaviyo, they unlock flow triggers that standard tracking can’t provide:

• Subscription renewal win-back: When Subscription Cancelled fires, trigger a win-back series based on how long they were subscribed
• Wishlist price drop: When wishlist items go on sale, notify customers who added them
• Membership upsell: When Membership Created fires at the basic tier, trigger an upgrade series after 30 days
• Review request timing: When Placed Order fires for a repeat customer, trigger review requests sooner than for first-time buyers

Custom events aren’t just data collection—they’re the foundation for behavioral targeting the standard plugin can’t achieve.

You may be interested in: Why Your Klaviyo WooCommerce Integration Keeps Breaking

The Implementation Gap

Klaviyo’s Track API documentation is excellent—for developers. It shows the endpoint, the authentication, the payload structure. What it doesn’t show is WooCommerce-specific implementation: which hooks to use, how to capture the data, how to format customer identifiers correctly.

Most store owners face a choice: hire a developer to write custom PHP that hooks into WooCommerce and sends properly formatted Track API calls, or accept the limitations of the 8 standard events.

There’s a third option. Transmute Engine™ routes WooCommerce events to Klaviyo’s Track API without custom code. Subscription renewals, membership changes, and custom actions fire through WooCommerce hooks, get captured server-side, and reach Klaviyo as properly formatted custom events. Same Track API, no development required.

Key Takeaways

• Official Klaviyo plugin tracks only 8 events—subscription, membership, and wishlist actions are not included
• Track API accepts unlimited custom event types with any properties you define
• Server-side Track API calls bypass ad blockers that block Klaviyo’s JavaScript on 31.5% of browsers
• WooCommerce hooks provide trigger points for capturing custom events at the moment they occur
• Custom events unlock advanced Klaviyo flows for subscription win-backs, wishlist alerts, membership upsells, and behavioral targeting

Your Klaviyo flows are only as good as the events that trigger them. Explore Transmute Engine for custom Klaviyo events without custom code.