diff --git a/include/MqttSettings.h b/include/MqttSettings.h
index 209a8ad..afa3283 100644
--- a/include/MqttSettings.h
+++ b/include/MqttSettings.h
@@ -13,8 +13,8 @@ public:
     void init();
     void performReconnect();
     bool getConnected();
-    void publish(String subtopic, String payload);
-    void publishHass(String subtopic, String payload);
+    void publish(const String& subtopic, const String& payload);
+    void publishHass(const String& subtopic, const String& payload);
 
     String getPrefix();
 
diff --git a/src/MqttSettings.cpp b/src/MqttSettings.cpp
index d7e7a65..516409b 100644
--- a/src/MqttSettings.cpp
+++ b/src/MqttSettings.cpp
@@ -233,14 +233,14 @@ String MqttSettingsClass::getPrefix()
     return Configuration.get().Mqtt_Topic;
 }
 
-void MqttSettingsClass::publish(String subtopic, String payload)
+void MqttSettingsClass::publish(const String& subtopic, const String& payload)
 {
     String topic = getPrefix();
     topic += subtopic;
     mqttClient->publish(topic.c_str(), 0, Configuration.get().Mqtt_Retain, payload.c_str());
 }
 
-void MqttSettingsClass::publishHass(String subtopic, String payload)
+void MqttSettingsClass::publishHass(const String& subtopic, const String& payload)
 {
     String topic = Configuration.get().Mqtt_Hass_Topic;
     topic += subtopic;