diff --git a/src/common/entity/compute_attribute_display.ts b/src/common/entity/compute_attribute_display.ts
index b3da42c10b..bee5735f01 100644
--- a/src/common/entity/compute_attribute_display.ts
+++ b/src/common/entity/compute_attribute_display.ts
@@ -34,7 +34,7 @@ export const computeAttributeValueDisplay = (
     value !== undefined ? value : stateObj.attributes[attribute];
 
   // Null value, the state is unknown
-  if (attributeValue === null) {
+  if (attributeValue === null || attributeValue === undefined) {
     return localize("state.default.unknown");
   }