Full Answer

The comparison depends entirely on whether email is a newsletter channel or a revenue channel for the store.

Mailchimp excels at content distribution. Its email builder is intuitive, template library is extensive, and pricing starts lower than Klaviyo at small subscriber counts. For WooCommerce stores that primarily send weekly newsletters, product announcements, or blog digest emails, Mailchimp handles the job without unnecessary complexity.

Klaviyo excels at revenue generation. Its core advantage is ecommerce-native segmentation — segments built from purchase recency, order frequency, average order value, product category affinity, and predicted churn risk. These segments power automated flows that trigger on behavioral events rather than calendar schedules. An abandoned cart flow, a post-purchase cross-sell sequence, and a win-back campaign for lapsing customers can run simultaneously, each targeting a different behavioral segment with different messaging.

The WooCommerce integration gap is significant. Klaviyo's official WooCommerce plugin syncs orders server-side, captures browsing behavior client-side, and maintains real-time customer profiles. Mailchimp's WooCommerce integration relies on a third-party plugin after Intuit discontinued the native connector in 2019. The third-party solution works but does not match the depth of data sync or the reliability of Klaviyo's first-party plugin.

Pricing follows a predictable pattern. Mailchimp is cheaper below 5,000 subscribers. Between 5,000 and 50,000, the gap narrows. Above 50,000, Klaviyo's per-contact pricing can be significantly higher. The decision metric should be revenue per email subscriber — if Klaviyo's better segmentation and flows generate more revenue per subscriber than the price difference, the higher cost is justified.