
Reviewers call Klaviyo expensive far more often than Mailchimp. Ecommerce teams keep paying because the real contest is not software cost - it is what each subscriber is worth.

Mailchimp is the cheaper, friendlier default. Klaviyo makes its higher bill defensible when a store can turn live shopping behavior into timely, profitable messages.
Revamp is a San Francisco startup (YC Summer 2023) that builds AI agents for eCommerce retention marketing. It plugs into Klaviyo and Shopify to turn scattered customer data into smart segments and then writes genuinely 1:1 personalized emails - drawing on signals like location, weather, purchase history and browsing behavior - so D2C brands can lift email revenue without hiring an army of copywriters.