diff --git a/services/npmplus.py b/services/npmplus.py
index 828ae0b..6418ed9 100644
--- a/services/npmplus.py
+++ b/services/npmplus.py
@@ -14,8 +14,12 @@ def _parse_expiry(value: str | None) -> datetime | None:
     cleaned = value.strip()
     try:
         if cleaned.endswith("Z"):
-            return datetime.fromisoformat(cleaned.replace("Z", "+00:00"))
-        return datetime.fromisoformat(cleaned)
+            dt = datetime.fromisoformat(cleaned.replace("Z", "+00:00"))
+        else:
+            dt = datetime.fromisoformat(cleaned)
+        if dt.tzinfo is None:
+            dt = dt.replace(tzinfo=timezone.utc)
+        return dt
     except ValueError:
         for fmt in ("%Y-%m-%d %H:%M:%S", "%Y-%m-%d"):
             try: