Let's Encrypt cuts certificate lifetimes to 64 days starting February 2027

Let's Encrypt has announced a significant update to its security protocols, reducing the validity period of its free SSL/TLS certificates from 90 days to 64 days. This change is scheduled to take effect on February 10, 2027. The initiative aims to further promote automated security practices across the web. Administrators currently utilizing modern ACME clients with ACME Renewal Information (ARI) support should experience a seamless transition. However, those relying on manual processes or hardcoded renewal schedules are urged to update their systems to prevent unexpected service interruptions. Testing for the new 64-day duration will commence on October 14, 2026, allowing users to verify their infrastructure compatibility before the official rollout. This move continues the organization's long-standing mission to enforce robust HTTPS encryption by mandating frequent, automated certificate renewals, a stark contrast to the multi-year certificates common before the service's inception in 2016.