diff --git a/checkmk/custom-files/local/monitor-os-expiry b/checkmk/custom-files/local/monitor-os-expiry
index 7ee261d66dfe2ec3734bbb26ea6cfe70403a58f7..ace3e66810be905d10182b1c45f793a718905b64 100644
--- a/checkmk/custom-files/local/monitor-os-expiry
+++ b/checkmk/custom-files/local/monitor-os-expiry
@@ -23,6 +23,8 @@ elif [[ $OS =~ ^Debian[[:space:]]10 ]]; then
     expiredate="2024-06-30"
 elif [[ $OS =~ ^Debian[[:space:]]11 ]]; then
     expiredate="2026-06-30"
+elif [[ $OS =~ ^Debian[[:space:]]12 ]]; then
+    expiredate="2028-06-30"
 elif [[ $OS =~ ^Ubuntu[[:space:]]18\.04 ]]; then
     expiredate="2023-04-30"
 elif [[ $OS =~ ^Ubuntu[[:space:]]20\.04 ]]; then