Examples / CRM and marketing / Mailchimp

Mailchimp webhooks

Audience changes: subscribe, unsubscribe, profile update, email change, campaign sent.

Events

subscribe
unsubscribe
profile
upemail
campaign

Signature

No signature. Put a secret in the webhook URL query string and check it. Mailchimp sends form-encoded bodies.

Retries

Mailchimp retries a few times over a short period.

See a retry schedule in the calculator.

Docs

mailchimp.com/developer/marketing/guides/sync-audience-da...

Checked 2026-10-08. Report a change.

Sample request from Mailchimpillustrative, shortened

Content-Typeapplication/x-www-form-urlencodedUser-AgentMailChimp

type=subscribe
fired_at=2026-10-08+06%3A34%3A00
data%5Bid%5D=8a25ff1d98
data%5Bemail%5D=ravi%40example.com
data%5Blist_id%5D=a6b5da1054
data%5Bmerges%5D%5BFNAME%5D=Ravi

Mailchimp sends a GET first to validate the URL. Return 200.

Receive Mailchimp webhooks with webhooks.xyz

Create a bin. Paste its URL into Mailchimp. Each request shows at once with its headers and body. Add your server as a destination, and deliveries retry when it is down. Request an invite.

More in crm and marketing: HubSpot, Salesforce (Outbound Messages).