Changes to when Automated Certificate Management renews certificates
Change effective on 10 November 2026
Starting November 16, 2026, Automated Certificate Management (ACM) checks with Let’s Encrypt when to renew each certificate. It uses ACME Renewal Information (ARI), a standard way for Let’s Encrypt to suggest a renewal time for each certificate (RFC 9773). We’re rolling out this change to apps in stages. No action is required.
ACM still renews certificates one month before they expire. If Let’s Encrypt suggests renewing sooner, for example before it revokes certificates, ACM renews in the suggested time. Some certificates renew earlier than before. Each domain keeps serving its current certificate until the new one is ready.
To see when your app’s certificates expire, run the command:
$ heroku certs -a example-app
For more information, see the Certificate Renewal section for ACM.