diff --git a/lib/spack/spack/operating_systems/mac_os.py b/lib/spack/spack/operating_systems/mac_os.py
index d52885fd54..01113a0cf9 100644
--- a/lib/spack/spack/operating_systems/mac_os.py
+++ b/lib/spack/spack/operating_systems/mac_os.py
@@ -143,6 +143,7 @@ def __init__(self):
             "12": "monterey",
             "13": "ventura",
             "14": "sonoma",
+            "15": "sequoia",
         }
 
         version = macos_version()