How Long are TLS/SSL Certificate Validity Periods?
TLS/SSL Certificate Validity Periods are currently 398 days, or about 13 months. They were recently reduced by the CA/B Forum starting Sept. 1, 2020 in response to Apple’s announcement stating they would not accept certificates for two-year validity periods. DigiCert has instituted a 397-day validity period in order to account for time zone differences.
As a response to shortened validity periods, DigiCert has introduced TLS/SSL certificate Multi-year Plans that allow for up to six years of TLS/SSL certificate coverage provided that the certificate is revalidated and reissued every year.