Webhooks overview (Pro)

Send new subscriber events to HTTPS endpoints you control or to supported ESP adapters.

Last reviewed: 2026-05-07

On Pro, Mailing list includes Webhooks. Each webhook stores:

  • A destination URL (HTTPS recommended).
  • An adapter that shapes the JSON payload for tools such as Klaviyo, Mailchimp, ConvertKit, Beehiiv, or a generic JSON POST you handle yourself.

Use Test after saving to confirm your endpoint returns success for a sample payload. fanmigo records delivery outcomes so you can tell whether failures are on your side or ours.

Rotate URLs if a secret leaks—delete the old webhook and create a new one with fresh credentials.