From a952e7236b13f83c3946a75d94597675d22ce893 Mon Sep 17 00:00:00 2001
From: "J. Nick Koston" <nick@home-assistant.io>
Date: Thu, 10 Sep 2026 16:04:57 -0500
Subject: [PATCH] [sensor] Only store raw state when filters are compiled in

---
 esphome/components/sensor/sensor.cpp |  7 ++-----
 esphome/components/sensor/sensor.h   | 11 ++++++++---
 2 files changed, 10 insertions(+), 8 deletions(-)

diff --git a/esphome/components/sensor/sensor.cpp b/esphome/components/sensor/sensor.cpp
index c83cb483df..bee5d7c6d3 100644
--- a/esphome/components/sensor/sensor.cpp
+++ b/esphome/components/sensor/sensor.cpp
@@ -40,10 +40,7 @@ const LogString *state_class_to_string(StateClass state_class) {
   return StateClassStrings::get_log_str(static_cast<uint8_t>(state_class), 0);
 }
 
-#pragma GCC diagnostic push
-#pragma GCC diagnostic ignored "-Wdeprecated-declarations"
-Sensor::Sensor() : state(NAN), raw_state_(NAN) {}
-#pragma GCC diagnostic pop
+Sensor::Sensor() : state(NAN) {}
 
 int8_t Sensor::get_accuracy_decimals() {
   if (this->sensor_flags_.has_accuracy_override)
@@ -66,8 +63,8 @@ StateClass Sensor::get_state_class() {
 }
 
 void Sensor::publish_state(float state) {
-  this->raw_state_ = state;
 #ifdef USE_SENSOR_FILTER
+  this->raw_state_ = state;
   this->raw_callback_.call(state);
 #endif
 
diff --git a/esphome/components/sensor/sensor.h b/esphome/components/sensor/sensor.h
index 8c0c479463..594cd22e55 100644
--- a/esphome/components/sensor/sensor.h
+++ b/esphome/components/sensor/sensor.h
@@ -97,7 +97,13 @@ class Sensor : public EntityBase {
   /// Getter-syntax for .state.
   float get_state() const { return this->state; }
   /// Get the last state received by publish_state(), before any filters were applied.
-  float get_raw_state() const { return this->raw_state_; }
+  float get_raw_state() const {
+#ifdef USE_SENSOR_FILTER
+    return this->raw_state_;
+#else
+    return this->state;  // No filters compiled in, raw == filtered
+#endif
+  }
 
   /** Publish a new state to the front-end.
    *
@@ -135,9 +141,8 @@ class Sensor : public EntityBase {
   void internal_send_state_to_frontend(float state);
 
  protected:
-  float raw_state_;  ///< The last state passed to publish_state(), before filters.
-
 #ifdef USE_SENSOR_FILTER
+  float raw_state_{NAN};                           ///< The last state passed to publish_state(), before filters.
   LazyCallbackManager<void(float)> raw_callback_;  ///< Storage for raw state callbacks.
 #endif
   LazyCallbackManager<void(float)> callback_;  ///< Storage for filtered state callbacks.