diff --git a/esphome/components/fan/fan.h b/esphome/components/fan/fan.h
index 2b76fa24da..eff57a343a 100644
--- a/esphome/components/fan/fan.h
+++ b/esphome/components/fan/fan.h
@@ -132,15 +132,10 @@ class Fan : public EntityBase {
 
   /// Set the supported preset modes (stored on Fan, referenced by FanTraits via pointer).
   void set_supported_preset_modes(std::initializer_list<const char *> preset_modes) {
-    if (!this->supported_preset_modes_)
-      this->supported_preset_modes_ =
-          new std::vector<const char *>();  // NOLINT - intentional leak, entity lives forever
-    *this->supported_preset_modes_ = preset_modes;
+    this->ensure_preset_modes_().assign(preset_modes.begin(), preset_modes.end());
   }
   void set_supported_preset_modes(const std::vector<const char *> &preset_modes) {
-    if (!this->supported_preset_modes_)
-      this->supported_preset_modes_ = new std::vector<const char *>();  // NOLINT
-    *this->supported_preset_modes_ = preset_modes;
+    this->ensure_preset_modes_() = preset_modes;
   }
 
   /// Set the restore mode of this fan.
@@ -184,7 +179,14 @@ class Fan : public EntityBase {
   ESPPreferenceObject rtc_;
   FanRestoreMode restore_mode_;
 
-  /// Preset mode storage — allocated on first use, never freed (entity lives forever).
+  /// Lazy-allocate preset modes vector (never freed — entity lives forever).
+  std::vector<const char *> &ensure_preset_modes_() {
+    if (!this->supported_preset_modes_) {
+      this->supported_preset_modes_ = new std::vector<const char *>();  // NOLINT
+    }
+    return *this->supported_preset_modes_;
+  }
+
   std::vector<const char *> *supported_preset_modes_{nullptr};
 
  private: