diff --git a/esphome/components/bedjet/bedjet_const.h b/esphome/components/bedjet/bedjet_const.h
index 0693be1092..10f403dd1a 100644
--- a/esphome/components/bedjet/bedjet_const.h
+++ b/esphome/components/bedjet/bedjet_const.h
@@ -100,7 +100,6 @@ enum BedjetCommand : uint8_t {
 static const uint8_t BEDJET_FAN_SPEED_COUNT = 20;
 
 static constexpr const char *const BEDJET_FAN_STEP_NAMES[BEDJET_FAN_SPEED_COUNT] = BEDJET_FAN_STEP_NAMES_;
-static const std::string BEDJET_FAN_STEP_NAME_STRINGS[BEDJET_FAN_SPEED_COUNT] = BEDJET_FAN_STEP_NAMES_;
 
 }  // namespace bedjet
 }  // namespace esphome
diff --git a/esphome/components/bedjet/climate/bedjet_climate.cpp b/esphome/components/bedjet/climate/bedjet_climate.cpp
index 877fd6f771..716d4d4241 100644
--- a/esphome/components/bedjet/climate/bedjet_climate.cpp
+++ b/esphome/components/bedjet/climate/bedjet_climate.cpp
@@ -8,15 +8,15 @@ namespace bedjet {
 
 using namespace esphome::climate;
 
-static const std::string *bedjet_fan_step_to_fan_mode(const uint8_t fan_step) {
+static const char *bedjet_fan_step_to_fan_mode(const uint8_t fan_step) {
   if (fan_step < BEDJET_FAN_SPEED_COUNT)
-    return &BEDJET_FAN_STEP_NAME_STRINGS[fan_step];
+    return BEDJET_FAN_STEP_NAMES[fan_step];
   return nullptr;
 }
 
-static uint8_t bedjet_fan_speed_to_step(const std::string &fan_step_percent) {
+static uint8_t bedjet_fan_speed_to_step(const char *fan_step_percent) {
   for (int i = 0; i < BEDJET_FAN_SPEED_COUNT; i++) {
-    if (fan_step_percent == BEDJET_FAN_STEP_NAME_STRINGS[i]) {
+    if (strcmp(BEDJET_FAN_STEP_NAMES[i], fan_step_percent) == 0) {
       return i;
     }
   }
@@ -163,27 +163,27 @@ void BedJetClimate::control(const ClimateCall &call) {
       ESP_LOGW(TAG, "Unsupported preset: %d", preset);
       return;
     }
-  } else if (call.get_custom_preset().has_value()) {
-    std::string preset = *call.get_custom_preset();
+  } else if (call.has_custom_preset()) {
+    const char *preset = call.get_custom_preset();
     bool result;
 
-    if (preset == "M1") {
+    if (strcmp(preset, "M1") == 0) {
       result = this->parent_->button_memory1();
-    } else if (preset == "M2") {
+    } else if (strcmp(preset, "M2") == 0) {
       result = this->parent_->button_memory2();
-    } else if (preset == "M3") {
+    } else if (strcmp(preset, "M3") == 0) {
       result = this->parent_->button_memory3();
-    } else if (preset == "LTD HT") {
+    } else if (strcmp(preset, "LTD HT") == 0) {
       result = this->parent_->button_heat();
-    } else if (preset == "EXT HT") {
+    } else if (strcmp(preset, "EXT HT") == 0) {
       result = this->parent_->button_ext_heat();
     } else {
-      ESP_LOGW(TAG, "Unsupported preset: %s", preset.c_str());
+      ESP_LOGW(TAG, "Unsupported preset: %s", preset);
       return;
     }
 
     if (result) {
-      this->set_custom_preset_(preset.c_str());
+      this->set_custom_preset_(preset);
     }
   }
 
@@ -207,15 +207,14 @@ void BedJetClimate::control(const ClimateCall &call) {
     if (result) {
       this->set_fan_mode_(fan_mode);
     }
-  } else if (call.get_custom_fan_mode().has_value()) {
-    auto fan_mode = *call.get_custom_fan_mode();
+  } else if (call.has_custom_fan_mode()) {
+    const char *fan_mode = call.get_custom_fan_mode();
     auto fan_index = bedjet_fan_speed_to_step(fan_mode);
     if (fan_index <= 19) {
-      ESP_LOGV(TAG, "[%s] Converted fan mode %s to bedjet fan step %d", this->get_name().c_str(), fan_mode.c_str(),
-               fan_index);
+      ESP_LOGV(TAG, "[%s] Converted fan mode %s to bedjet fan step %d", this->get_name().c_str(), fan_mode, fan_index);
       bool result = this->parent_->set_fan_index(fan_index);
       if (result) {
-        this->set_custom_fan_mode_(fan_mode.c_str());
+        this->set_custom_fan_mode_(fan_mode);
       }
     }
   }
@@ -241,7 +240,7 @@ void BedJetClimate::on_status(const BedjetStatusPacket *data) {
 
   const auto *fan_mode_name = bedjet_fan_step_to_fan_mode(data->fan_step);
   if (fan_mode_name != nullptr) {
-    this->set_custom_fan_mode_(fan_mode_name->c_str());
+    this->set_custom_fan_mode_(fan_mode_name);
   }
 
   // TODO: Get biorhythm data to determine which preset (M1-3) is running, if any.
diff --git a/esphome/components/climate/climate.cpp b/esphome/components/climate/climate.cpp
index e596582de8..7df38758dc 100644
--- a/esphome/components/climate/climate.cpp
+++ b/esphome/components/climate/climate.cpp
@@ -292,14 +292,6 @@ const optional<ClimateFanMode> &ClimateCall::get_fan_mode() const { return this-
 const optional<ClimateSwingMode> &ClimateCall::get_swing_mode() const { return this->swing_mode_; }
 const optional<ClimatePreset> &ClimateCall::get_preset() const { return this->preset_; }
 
-optional<std::string> ClimateCall::get_custom_fan_mode() const {
-  return this->custom_fan_mode_ != nullptr ? std::string(this->custom_fan_mode_) : optional<std::string>{};
-}
-
-optional<std::string> ClimateCall::get_custom_preset() const {
-  return this->custom_preset_ != nullptr ? std::string(this->custom_preset_) : optional<std::string>{};
-}
-
 ClimateCall &ClimateCall::set_target_temperature_high(optional<float> target_temperature_high) {
   this->target_temperature_high_ = target_temperature_high;
   return *this;
diff --git a/esphome/components/climate/climate.h b/esphome/components/climate/climate.h
index 091483a033..b277877c3e 100644
--- a/esphome/components/climate/climate.h
+++ b/esphome/components/climate/climate.h
@@ -107,8 +107,10 @@ class ClimateCall {
   const optional<ClimateFanMode> &get_fan_mode() const;
   const optional<ClimateSwingMode> &get_swing_mode() const;
   const optional<ClimatePreset> &get_preset() const;
-  optional<std::string> get_custom_fan_mode() const;
-  optional<std::string> get_custom_preset() const;
+  const char *get_custom_fan_mode() const { return this->custom_fan_mode_; }
+  const char *get_custom_preset() const { return this->custom_preset_; }
+  bool has_custom_fan_mode() const { return this->custom_fan_mode_ != nullptr; }
+  bool has_custom_preset() const { return this->custom_preset_ != nullptr; }
 
  protected:
   void validate_();
@@ -122,6 +124,8 @@ class ClimateCall {
   optional<ClimateFanMode> fan_mode_;
   optional<ClimateSwingMode> swing_mode_;
   optional<ClimatePreset> preset_;
+
+ private:
   const char *custom_fan_mode_{nullptr};
   const char *custom_preset_{nullptr};
 };
diff --git a/esphome/components/demo/demo_climate.h b/esphome/components/demo/demo_climate.h
index f8944b0735..e2dfb0142b 100644
--- a/esphome/components/demo/demo_climate.h
+++ b/esphome/components/demo/demo_climate.h
@@ -63,14 +63,14 @@ class DemoClimate : public climate::Climate, public Component {
     if (call.get_swing_mode().has_value()) {
       this->swing_mode = *call.get_swing_mode();
     }
-    if (call.get_custom_fan_mode().has_value()) {
-      this->set_custom_fan_mode_(call.get_custom_fan_mode()->c_str());
+    if (call.has_custom_fan_mode()) {
+      this->set_custom_fan_mode_(call.get_custom_fan_mode());
     }
     if (call.get_preset().has_value()) {
       this->set_preset_(*call.get_preset());
     }
-    if (call.get_custom_preset().has_value()) {
-      this->set_custom_preset_(call.get_custom_preset()->c_str());
+    if (call.has_custom_preset()) {
+      this->set_custom_preset_(call.get_custom_preset());
     }
     this->publish_state();
   }
diff --git a/esphome/components/midea/ac_adapter.cpp b/esphome/components/midea/ac_adapter.cpp
index dca4038f04..d903db4a1b 100644
--- a/esphome/components/midea/ac_adapter.cpp
+++ b/esphome/components/midea/ac_adapter.cpp
@@ -117,8 +117,8 @@ const char *Converters::to_custom_climate_fan_mode(MideaFanMode mode) {
   }
 }
 
-MideaFanMode Converters::to_midea_fan_mode(const std::string &mode) {
-  if (mode == Constants::SILENT)
+MideaFanMode Converters::to_midea_fan_mode(const char *mode) {
+  if (strcmp(mode, Constants::SILENT) == 0)
     return MideaFanMode::FAN_SILENT;
   return MideaFanMode::FAN_TURBO;
 }
@@ -153,7 +153,7 @@ bool Converters::is_custom_midea_preset(MideaPreset preset) { return preset == M
 
 const char *Converters::to_custom_climate_preset(MideaPreset preset) { return Constants::FREEZE_PROTECTION; }
 
-MideaPreset Converters::to_midea_preset(const std::string &preset) { return MideaPreset::PRESET_FREEZE_PROTECTION; }
+MideaPreset Converters::to_midea_preset(const char *preset) { return MideaPreset::PRESET_FREEZE_PROTECTION; }
 
 void Converters::to_climate_traits(ClimateTraits &traits, const dudanov::midea::ac::Capabilities &capabilities) {
   if (capabilities.supportAutoMode())
diff --git a/esphome/components/midea/ac_adapter.h b/esphome/components/midea/ac_adapter.h
index d52f421331..b0589a37f9 100644
--- a/esphome/components/midea/ac_adapter.h
+++ b/esphome/components/midea/ac_adapter.h
@@ -32,12 +32,12 @@ class Converters {
   static MideaSwingMode to_midea_swing_mode(ClimateSwingMode mode);
   static ClimateSwingMode to_climate_swing_mode(MideaSwingMode mode);
   static MideaPreset to_midea_preset(ClimatePreset preset);
-  static MideaPreset to_midea_preset(const std::string &preset);
+  static MideaPreset to_midea_preset(const char *preset);
   static bool is_custom_midea_preset(MideaPreset preset);
   static ClimatePreset to_climate_preset(MideaPreset preset);
   static const char *to_custom_climate_preset(MideaPreset preset);
   static MideaFanMode to_midea_fan_mode(ClimateFanMode fan_mode);
-  static MideaFanMode to_midea_fan_mode(const std::string &fan_mode);
+  static MideaFanMode to_midea_fan_mode(const char *fan_mode);
   static bool is_custom_midea_fan_mode(MideaFanMode fan_mode);
   static ClimateFanMode to_climate_fan_mode(MideaFanMode fan_mode);
   static const char *to_custom_climate_fan_mode(MideaFanMode fan_mode);
diff --git a/esphome/components/midea/air_conditioner.cpp b/esphome/components/midea/air_conditioner.cpp
index 97eacb936c..a6a8d52549 100644
--- a/esphome/components/midea/air_conditioner.cpp
+++ b/esphome/components/midea/air_conditioner.cpp
@@ -64,13 +64,13 @@ void AirConditioner::control(const ClimateCall &call) {
     ctrl.mode = Converters::to_midea_mode(call.get_mode().value());
   if (call.get_preset().has_value()) {
     ctrl.preset = Converters::to_midea_preset(call.get_preset().value());
-  } else if (call.get_custom_preset().has_value()) {
-    ctrl.preset = Converters::to_midea_preset(call.get_custom_preset().value());
+  } else if (call.has_custom_preset()) {
+    ctrl.preset = Converters::to_midea_preset(call.get_custom_preset());
   }
   if (call.get_fan_mode().has_value()) {
     ctrl.fanMode = Converters::to_midea_fan_mode(call.get_fan_mode().value());
-  } else if (call.get_custom_fan_mode().has_value()) {
-    ctrl.fanMode = Converters::to_midea_fan_mode(call.get_custom_fan_mode().value());
+  } else if (call.has_custom_fan_mode()) {
+    ctrl.fanMode = Converters::to_midea_fan_mode(call.get_custom_fan_mode());
   }
   this->base_.control(ctrl);
 }
diff --git a/esphome/components/thermostat/thermostat_climate.cpp b/esphome/components/thermostat/thermostat_climate.cpp
index 8258fa9d65..d533ef93ec 100644
--- a/esphome/components/thermostat/thermostat_climate.cpp
+++ b/esphome/components/thermostat/thermostat_climate.cpp
@@ -54,7 +54,7 @@ void ThermostatClimate::setup() {
     if (this->default_preset_ != climate::ClimatePreset::CLIMATE_PRESET_NONE) {
       this->change_preset_(this->default_preset_);
     } else if (!this->default_custom_preset_.empty()) {
-      this->change_custom_preset_(this->default_custom_preset_);
+      this->change_custom_preset_(this->default_custom_preset_.c_str());
     }
   }
 
@@ -218,13 +218,13 @@ void ThermostatClimate::control(const climate::ClimateCall &call) {
       this->preset = call.get_preset().value();
     }
   }
-  if (call.get_custom_preset().has_value()) {
+  if (call.has_custom_preset()) {
     // setup_complete_ blocks modifying/resetting the temps immediately after boot
     if (this->setup_complete_) {
-      this->change_custom_preset_(call.get_custom_preset().value());
+      this->change_custom_preset_(call.get_custom_preset());
     } else {
       // Use the base class method which handles pointer lookup internally
-      this->set_custom_preset_(call.get_custom_preset().value().c_str());
+      this->set_custom_preset_(call.get_custom_preset());
     }
   }
 
@@ -1177,31 +1177,31 @@ void ThermostatClimate::change_preset_(climate::ClimatePreset preset) {
   }
 }
 
-void ThermostatClimate::change_custom_preset_(const std::string &custom_preset) {
+void ThermostatClimate::change_custom_preset_(const char *custom_preset) {
   auto config = this->custom_preset_config_.find(custom_preset);
 
   if (config != this->custom_preset_config_.end()) {
-    ESP_LOGV(TAG, "Custom preset %s requested", custom_preset.c_str());
+    ESP_LOGV(TAG, "Custom preset %s requested", custom_preset);
     if (this->change_preset_internal_(config->second) || !this->has_custom_preset() ||
-        strcmp(this->get_custom_preset(), custom_preset.c_str()) != 0) {
+        strcmp(this->get_custom_preset(), custom_preset) != 0) {
       // Fire any preset changed trigger if defined
       Trigger<> *trig = this->preset_change_trigger_;
       // Use the base class method which handles pointer lookup and preset reset internally
-      this->set_custom_preset_(custom_preset.c_str());
+      this->set_custom_preset_(custom_preset);
       if (trig != nullptr) {
         trig->trigger();
       }
 
       this->refresh();
-      ESP_LOGI(TAG, "Custom preset %s applied", custom_preset.c_str());
+      ESP_LOGI(TAG, "Custom preset %s applied", custom_preset);
     } else {
-      ESP_LOGI(TAG, "No changes required to apply custom preset %s", custom_preset.c_str());
+      ESP_LOGI(TAG, "No changes required to apply custom preset %s", custom_preset);
+      // Note: set_custom_preset_() above handles preset.reset() and custom_preset_ assignment internally.
+      // The old code had these lines here unconditionally, which was a bug (double assignment, state modification
+      // even when no changes were needed). Now properly handled by the protected setter with mutual exclusion.
     }
-    // Note: set_custom_preset_() above handles preset.reset() and custom_preset_ assignment internally.
-    // The old code had these lines here unconditionally, which was a bug (double assignment, state modification
-    // even when no changes were needed). Now properly handled by the protected setter with mutual exclusion.
   } else {
-    ESP_LOGW(TAG, "Custom preset %s not configured; ignoring", custom_preset.c_str());
+    ESP_LOGW(TAG, "Custom preset %s not configured; ignoring", custom_preset);
   }
 }
 
diff --git a/esphome/components/thermostat/thermostat_climate.h b/esphome/components/thermostat/thermostat_climate.h
index 42adab7751..c9795d9666 100644
--- a/esphome/components/thermostat/thermostat_climate.h
+++ b/esphome/components/thermostat/thermostat_climate.h
@@ -199,7 +199,7 @@ class ThermostatClimate : public climate::Climate, public Component {
   /// Change to a provided preset setting; will reset temperature, mode, fan, and swing modes accordingly
   void change_preset_(climate::ClimatePreset preset);
   /// Change to a provided custom preset setting; will reset temperature, mode, fan, and swing modes accordingly
-  void change_custom_preset_(const std::string &custom_preset);
+  void change_custom_preset_(const char *custom_preset);
 
   /// Applies the temperature, mode, fan, and swing modes of the provided config.
   /// This is agnostic of custom vs built in preset
diff --git a/requirements.txt b/requirements.txt
index 660b18c933..33fa2b64eb 100644
--- a/requirements.txt
+++ b/requirements.txt
@@ -12,7 +12,7 @@ platformio==6.1.18  # When updating platformio, also update /docker/Dockerfile
 esptool==5.1.0
 click==8.1.7
 esphome-dashboard==20251013.0
-aioesphomeapi==42.5.0
+aioesphomeapi==42.6.0
 zeroconf==0.148.0
 puremagic==1.30
 ruamel.yaml==0.18.16 # dashboard_import