diff --git a/esphome/core/entity_base.h b/esphome/core/entity_base.h
index 869981eb7a..d03326ccf8 100644
--- a/esphome/core/entity_base.h
+++ b/esphome/core/entity_base.h
@@ -347,27 +347,26 @@ template<typename T> class StatefulEntityBase : public EntityBase {
   virtual bool set_new_state(const optional<T> &new_state) {
     // Access flags_ directly to avoid function call overhead in this hot path
     bool had_state = this->flags_.has_state;
-    // Cache get_state() result to avoid calling the virtual method twice
-    T current{};
-    if (had_state)
-      current = this->get_state();
+    // Use pointer to avoid requiring T to be default-constructible
+    const T *current = had_state ? &this->get_state() : nullptr;
     if (new_state.has_value()) {
-      if (had_state && current == new_state.value())
+      if (current != nullptr && *current == new_state.value())
         return false;  // same value, no change
     } else if (!had_state) {
       return false;  // already invalidated, no change
     }
-    // State changed — update storage before firing callbacks so callback code
-    // can inspect the entity's current state via get_state()/has_state()
+    // Capture old_state before set_state_value — current pointer aliases subclass storage
+    bool has_full_cbs = !this->full_state_callbacks_.empty();
+    optional<T> old_state;
+    if (has_full_cbs)
+      old_state = current != nullptr ? optional<T>(*current) : nullopt;
+    // Update storage before firing callbacks so callback code can inspect current state
     this->flags_.has_state = new_state.has_value();
     if (new_state.has_value()) {
       this->set_state_value(new_state.value());
     }
-    // Only construct old_state and call full_state_callbacks when callbacks are registered
-    if (!this->full_state_callbacks_.empty()) {
-      optional<T> old_state = had_state ? optional<T>(current) : nullopt;
+    if (has_full_cbs)
       this->full_state_callbacks_.call(old_state, new_state);
-    }
     // had_state first: on every change except the first, skips the virtual call
     if (new_state.has_value() && (had_state || this->get_trigger_on_initial_state()))
       this->state_callbacks_.call(new_state.value());