This site states this directly: Gelagen is a one-time purchase with no automatic renewals or hidden fees.
Recurring, hard-to-cancel subscriptions are a common complaint in the supplement category generally — worth crediting this site's direct no-auto-billing claim, while still confirming it yourself at checkout before you pay.
This site's own FAQ is direct: confirm this directly at checkout, since terms can change — worth checking the actual checkout page rather than relying on the homepage claim alone.