diff --git a/esphome/components/esp32_ble/ble.cpp b/esphome/components/esp32_ble/ble.cpp
index edf6f3254b..3b561883f8 100644
--- a/esphome/components/esp32_ble/ble.cpp
+++ b/esphome/components/esp32_ble/ble.cpp
@@ -338,11 +338,12 @@ void ESP32BLE::loop() {
                    gap_event == ESP_GAP_BLE_SCAN_START_COMPLETE_EVT ||
                    gap_event == ESP_GAP_BLE_SCAN_STOP_COMPLETE_EVT) {
           // All three scan complete events have the same structure with just status
-          // Cast is safe because all three ESP-IDF event structures are identical with just status field
-          // The scan_complete struct already contains our copy of the status (copied in BLEEvent constructor)
+          // The scan_complete struct matches ESP-IDF's layout exactly, so this reinterpret_cast is safe
+          // The struct already contains our copy of the status (copied in BLEEvent constructor)
           ESP_LOGV(TAG, "gap_event_handler - %d", gap_event);
           for (auto *gap_handler : this->gap_event_handlers_) {
-            gap_handler->gap_event_handler(gap_event, (esp_ble_gap_cb_param_t *) &ble_event->event_.gap.scan_complete);
+            gap_handler->gap_event_handler(
+                gap_event, reinterpret_cast<esp_ble_gap_cb_param_t *>(&ble_event->event_.gap.scan_complete));
           }
         }
         break;
diff --git a/esphome/components/esp32_ble/ble_event.h b/esphome/components/esp32_ble/ble_event.h
index eb6453801f..e0178c41db 100644
--- a/esphome/components/esp32_ble/ble_event.h
+++ b/esphome/components/esp32_ble/ble_event.h
@@ -157,7 +157,9 @@ class BLEEvent {
       esp_gap_ble_cb_event_t gap_event;
       union {
         BLEScanResult scan_result;  // 73 bytes
-        struct {
+        // This struct matches ESP-IDF's scan complete event structures
+        // All three (scan_param_cmpl, scan_start_cmpl, scan_stop_cmpl) have identical layout
+        struct ble_scan_complete_evt_param {
           esp_bt_status_t status;
         } scan_complete;  // 1 byte
       };
diff --git a/esphome/components/esp32_ble/ble_scan_result.h b/esphome/components/esp32_ble/ble_scan_result.h
index 42e1789437..49b0d5523d 100644
--- a/esphome/components/esp32_ble/ble_scan_result.h
+++ b/esphome/components/esp32_ble/ble_scan_result.h
@@ -8,7 +8,7 @@ namespace esphome {
 namespace esp32_ble {
 
 // Structure for BLE scan results - only fields we actually use
-struct BLEScanResult {
+struct __attribute__((packed)) BLEScanResult {
   esp_bd_addr_t bda;
   uint8_t ble_addr_type;
   int8_t rssi;