Kit (formerly ConvertKit) is the automation-first option in this comparison. The mental model is closer to a lightweight CRM than a publishing tool: subscribers are tagged, segmented, and routed through sequences based on what they actually do.
That makes it ideal when your business is a product first and a newsletter second — for example, a course creator who wants the welcome sequence to branch based on quiz answers, or an indie SaaS founder running a trial-to-paid drip. Beehiiv and Substack assume you’re publishing on a schedule and want growth to come from the network; Kit assumes you’re building a funnel and want growth to come from referrals and conversion.
The honest trade-off: the editor and dashboards feel a generation behind newer entrants. If you fall in love with Beehiiv’s writing experience, Kit will feel utilitarian. If you fall in love with Kit’s automation graph, Beehiiv will feel limiting. Pick the one whose daily friction you’d rather live with.