diff --git a/esphome/components/prometheus/prometheus_handler.cpp b/esphome/components/prometheus/prometheus_handler.cpp
index 9ae4a74718..88b357041a 100644
--- a/esphome/components/prometheus/prometheus_handler.cpp
+++ b/esphome/components/prometheus/prometheus_handler.cpp
@@ -116,8 +116,7 @@ std::string PrometheusHandler::relabel_id_(EntityBase *obj) {
     return item->second;
   }
   char object_id_buf[OBJECT_ID_MAX_LEN];
-  StringRef object_id = obj->get_object_id_to(object_id_buf);
-  return object_id.str();
+  return obj->get_object_id_to(object_id_buf).str();
 }
 
 std::string PrometheusHandler::relabel_name_(EntityBase *obj) {