The Billing page is where patients manage payment methods. Access via Billing in the left sidebar.
The page ("Payment methods") lets patients + Add another card. Cards are grouped into Default card (used for automatic payments — with Default and Remove actions) and Other cards (available for manual use — with Make Default and Remove). A "Secure by design" note states cards are tokenized and never stored on servers, and shows the active gateway.
What operators should know: the default card is charged automatically for renewals — if a renewal fails, check whether it's expired or underfunded; patients can save multiple cards; the gateway shown reflects Settings > Payments (switching gateways means saved cards don't transfer); if a patient can't add a card, check your gateway config and that the environment is Production (Live).