diff --git a/esphome/components/mqtt/mqtt_climate.cpp b/esphome/components/mqtt/mqtt_climate.cpp
index 158cfb5552..b551f4b8a7 100644
--- a/esphome/components/mqtt/mqtt_climate.cpp
+++ b/esphome/components/mqtt/mqtt_climate.cpp
@@ -300,9 +300,11 @@ const EntityBase *MQTTClimateComponent::get_entity() const { return this->device
 
 bool MQTTClimateComponent::publish_state_() {
   auto traits = this->device_->get_traits();
+  // Reusable stack buffer for topic construction (avoids heap allocation per publish)
+  char topic_buf[MQTT_DEFAULT_TOPIC_MAX_LEN];
   // mode
   bool success = true;
-  if (!this->publish(this->get_mode_state_topic(), climate_mode_to_mqtt_str(this->device_->mode)))
+  if (!this->publish(this->get_mode_state_topic_to(topic_buf), climate_mode_to_mqtt_str(this->device_->mode)))
     success = false;
   int8_t target_accuracy = traits.get_target_temperature_accuracy_decimals();
   int8_t current_accuracy = traits.get_current_temperature_accuracy_decimals();
@@ -311,68 +313,70 @@ bool MQTTClimateComponent::publish_state_() {
   if (traits.has_feature_flags(climate::CLIMATE_SUPPORTS_CURRENT_TEMPERATURE) &&
       !std::isnan(this->device_->current_temperature)) {
     len = value_accuracy_to_buf(payload, this->device_->current_temperature, current_accuracy);
-    if (!this->publish(this->get_current_temperature_state_topic(), payload, len))
+    if (!this->publish(this->get_current_temperature_state_topic_to(topic_buf), payload, len))
       success = false;
   }
   if (traits.has_feature_flags(climate::CLIMATE_SUPPORTS_TWO_POINT_TARGET_TEMPERATURE |
                                climate::CLIMATE_REQUIRES_TWO_POINT_TARGET_TEMPERATURE)) {
     len = value_accuracy_to_buf(payload, this->device_->target_temperature_low, target_accuracy);
-    if (!this->publish(this->get_target_temperature_low_state_topic(), payload, len))
+    if (!this->publish(this->get_target_temperature_low_state_topic_to(topic_buf), payload, len))
       success = false;
     len = value_accuracy_to_buf(payload, this->device_->target_temperature_high, target_accuracy);
-    if (!this->publish(this->get_target_temperature_high_state_topic(), payload, len))
+    if (!this->publish(this->get_target_temperature_high_state_topic_to(topic_buf), payload, len))
       success = false;
   } else {
     len = value_accuracy_to_buf(payload, this->device_->target_temperature, target_accuracy);
-    if (!this->publish(this->get_target_temperature_state_topic(), payload, len))
+    if (!this->publish(this->get_target_temperature_state_topic_to(topic_buf), payload, len))
       success = false;
   }
 
   if (traits.has_feature_flags(climate::CLIMATE_SUPPORTS_CURRENT_HUMIDITY) &&
       !std::isnan(this->device_->current_humidity)) {
     len = value_accuracy_to_buf(payload, this->device_->current_humidity, 0);
-    if (!this->publish(this->get_current_humidity_state_topic(), payload, len))
+    if (!this->publish(this->get_current_humidity_state_topic_to(topic_buf), payload, len))
       success = false;
   }
   if (traits.has_feature_flags(climate::CLIMATE_SUPPORTS_TARGET_HUMIDITY) &&
       !std::isnan(this->device_->target_humidity)) {
     len = value_accuracy_to_buf(payload, this->device_->target_humidity, 0);
-    if (!this->publish(this->get_target_humidity_state_topic(), payload, len))
+    if (!this->publish(this->get_target_humidity_state_topic_to(topic_buf), payload, len))
       success = false;
   }
 
   if (traits.get_supports_presets() || !traits.get_supported_custom_presets().empty()) {
     if (this->device_->has_custom_preset()) {
-      if (!this->publish(this->get_preset_state_topic(), this->device_->get_custom_preset()))
+      if (!this->publish(this->get_preset_state_topic_to(topic_buf), this->device_->get_custom_preset()))
         success = false;
     } else if (this->device_->preset.has_value()) {
-      if (!this->publish(this->get_preset_state_topic(), climate_preset_to_mqtt_str(this->device_->preset.value())))
+      if (!this->publish(this->get_preset_state_topic_to(topic_buf),
+                         climate_preset_to_mqtt_str(this->device_->preset.value())))
         success = false;
-    } else if (!this->publish(this->get_preset_state_topic(), "")) {
+    } else if (!this->publish(this->get_preset_state_topic_to(topic_buf), "")) {
       success = false;
     }
   }
 
   if (traits.has_feature_flags(climate::CLIMATE_SUPPORTS_ACTION)) {
-    if (!this->publish(this->get_action_state_topic(), climate_action_to_mqtt_str(this->device_->action)))
+    if (!this->publish(this->get_action_state_topic_to(topic_buf), climate_action_to_mqtt_str(this->device_->action)))
       success = false;
   }
 
   if (traits.get_supports_fan_modes()) {
     if (this->device_->has_custom_fan_mode()) {
-      if (!this->publish(this->get_fan_mode_state_topic(), this->device_->get_custom_fan_mode()))
+      if (!this->publish(this->get_fan_mode_state_topic_to(topic_buf), this->device_->get_custom_fan_mode()))
         success = false;
     } else if (this->device_->fan_mode.has_value()) {
-      if (!this->publish(this->get_fan_mode_state_topic(),
+      if (!this->publish(this->get_fan_mode_state_topic_to(topic_buf),
                          climate_fan_mode_to_mqtt_str(this->device_->fan_mode.value())))
         success = false;
-    } else if (!this->publish(this->get_fan_mode_state_topic(), "")) {
+    } else if (!this->publish(this->get_fan_mode_state_topic_to(topic_buf), "")) {
       success = false;
     }
   }
 
   if (traits.get_supports_swing_modes()) {
-    if (!this->publish(this->get_swing_mode_state_topic(), climate_swing_mode_to_mqtt_str(this->device_->swing_mode)))
+    if (!this->publish(this->get_swing_mode_state_topic_to(topic_buf),
+                       climate_swing_mode_to_mqtt_str(this->device_->swing_mode)))
       success = false;
   }
 
diff --git a/esphome/components/mqtt/mqtt_component.h b/esphome/components/mqtt/mqtt_component.h
index 22c4618b55..7f3671d430 100644
--- a/esphome/components/mqtt/mqtt_component.h
+++ b/esphome/components/mqtt/mqtt_component.h
@@ -55,6 +55,11 @@ void log_mqtt_component(const char *tag, MQTTComponent *obj, bool state_topic, b
 \
  public: \
   void set_custom_##name##_##type##_topic(const std::string &topic) { this->custom_##name##_##type##_topic_ = topic; } \
+  StringRef get_##name##_##type##_topic_to(std::span<char, MQTT_DEFAULT_TOPIC_MAX_LEN> buf) const { \
+    if (!this->custom_##name##_##type##_topic_.empty()) \
+      return StringRef(this->custom_##name##_##type##_topic_.data(), this->custom_##name##_##type##_topic_.size()); \
+    return this->get_default_topic_for_to_(buf, #name "/" #type, sizeof(#name "/" #type) - 1); \
+  } \
   std::string get_##name##_##type##_topic() const { \
     if (this->custom_##name##_##type##_topic_.empty()) \
       return this->get_default_topic_for_(#name "/" #type); \
diff --git a/esphome/components/mqtt/mqtt_cover.cpp b/esphome/components/mqtt/mqtt_cover.cpp
index 50e68ecbcc..c21af413ed 100644
--- a/esphome/components/mqtt/mqtt_cover.cpp
+++ b/esphome/components/mqtt/mqtt_cover.cpp
@@ -112,19 +112,19 @@ bool MQTTCoverComponent::send_initial_state() { return this->publish_state(); }
 bool MQTTCoverComponent::publish_state() {
   auto traits = this->cover_->get_traits();
   bool success = true;
+  char topic_buf[MQTT_DEFAULT_TOPIC_MAX_LEN];
   if (traits.get_supports_position()) {
     char pos[VALUE_ACCURACY_MAX_LEN];
     size_t len = value_accuracy_to_buf(pos, roundf(this->cover_->position * 100), 0);
-    if (!this->publish(this->get_position_state_topic(), pos, len))
+    if (!this->publish(this->get_position_state_topic_to(topic_buf), pos, len))
       success = false;
   }
   if (traits.get_supports_tilt()) {
     char pos[VALUE_ACCURACY_MAX_LEN];
     size_t len = value_accuracy_to_buf(pos, roundf(this->cover_->tilt * 100), 0);
-    if (!this->publish(this->get_tilt_state_topic(), pos, len))
+    if (!this->publish(this->get_tilt_state_topic_to(topic_buf), pos, len))
       success = false;
   }
-  char topic_buf[MQTT_DEFAULT_TOPIC_MAX_LEN];
   if (!this->publish(this->get_state_topic_to_(topic_buf),
                      cover_state_to_mqtt_str(this->cover_->current_operation, this->cover_->position,
                                              traits.get_supports_position())))
diff --git a/esphome/components/mqtt/mqtt_fan.cpp b/esphome/components/mqtt/mqtt_fan.cpp
index 84d51895c5..ae2b8c4600 100644
--- a/esphome/components/mqtt/mqtt_fan.cpp
+++ b/esphome/components/mqtt/mqtt_fan.cpp
@@ -173,19 +173,20 @@ bool MQTTFanComponent::publish_state() {
   this->publish(this->get_state_topic_to_(topic_buf), state_s);
   bool failed = false;
   if (this->state_->get_traits().supports_direction()) {
-    bool success = this->publish(this->get_direction_state_topic(), fan_direction_to_mqtt_str(this->state_->direction));
+    bool success = this->publish(this->get_direction_state_topic_to(topic_buf),
+                                 fan_direction_to_mqtt_str(this->state_->direction));
     failed = failed || !success;
   }
   if (this->state_->get_traits().supports_oscillation()) {
-    bool success =
-        this->publish(this->get_oscillation_state_topic(), fan_oscillation_to_mqtt_str(this->state_->oscillating));
+    bool success = this->publish(this->get_oscillation_state_topic_to(topic_buf),
+                                 fan_oscillation_to_mqtt_str(this->state_->oscillating));
     failed = failed || !success;
   }
   auto traits = this->state_->get_traits();
   if (traits.supports_speed()) {
     char buf[12];
     size_t len = buf_append_printf(buf, sizeof(buf), 0, "%d", this->state_->speed);
-    bool success = this->publish(this->get_speed_level_state_topic(), buf, len);
+    bool success = this->publish(this->get_speed_level_state_topic_to(topic_buf), buf, len);
     failed = failed || !success;
   }
   return !failed;
diff --git a/esphome/components/mqtt/mqtt_valve.cpp b/esphome/components/mqtt/mqtt_valve.cpp
index 16e25f6a8a..2b9f02858b 100644
--- a/esphome/components/mqtt/mqtt_valve.cpp
+++ b/esphome/components/mqtt/mqtt_valve.cpp
@@ -87,13 +87,13 @@ bool MQTTValveComponent::send_initial_state() { return this->publish_state(); }
 bool MQTTValveComponent::publish_state() {
   auto traits = this->valve_->get_traits();
   bool success = true;
+  char topic_buf[MQTT_DEFAULT_TOPIC_MAX_LEN];
   if (traits.get_supports_position()) {
     char pos[VALUE_ACCURACY_MAX_LEN];
     size_t len = value_accuracy_to_buf(pos, roundf(this->valve_->position * 100), 0);
-    if (!this->publish(this->get_position_state_topic(), pos, len))
+    if (!this->publish(this->get_position_state_topic_to(topic_buf), pos, len))
       success = false;
   }
-  char topic_buf[MQTT_DEFAULT_TOPIC_MAX_LEN];
   if (!this->publish(this->get_state_topic_to_(topic_buf),
                      valve_state_to_mqtt_str(this->valve_->current_operation, this->valve_->position,
                                              traits.get_supports_position())))