Short version: as little as possible.
Your answers to the matching questionnaire stay in your browser. They are not sent to a server, not stored, and not associated with an identifier.
If you subscribe to pricing-change alerts, we store your email address for the sole purpose of sending you those alerts. You can unsubscribe from any email we send.
We may use privacy-respecting analytics (e.g. Plausible, Fathom) to count aggregate pageviews. We do not use tracking cookies for advertising.
When you click through to a provider, that provider's site sets its own cookies under its own privacy policy. We may receive a referral acknowledgement from the provider indicating a signup occurred; we do not receive your personal details from them.
Questions about this policy: reply to any email from us, or open an issue on our public issue tracker once available.