Reference
Tracking requires a custom tracking domain
Open and click tracking now works only with a verified tracking CNAME on your own domain. New mail no longer uses shared tracking links.
Updated Sep 27, 2026
ChangedOpen & click trackingSending domains
To track opens and clicks, publish a CNAME record from go.yourdomain.com (or your custom tracking subdomain) to go.emailitmail.com and verify it. The Track loads and Track clicks switches on a domain turn on only after the record is verified.
Links and open pixels in emails you sent earlier with shared tracking links keep working. See Custom tracking domain.