diff --git a/esphome/components/ota/ota_backend.h b/esphome/components/ota/ota_backend.h
index bc8ab46643..f488cba1f8 100644
--- a/esphome/components/ota/ota_backend.h
+++ b/esphome/components/ota/ota_backend.h
@@ -4,6 +4,15 @@
 #include "esphome/core/defines.h"
 #include "esphome/core/helpers.h"
 
+#include "ota_component.h"
+
+// Extended OTAState enum to include additional states needed by backends
+// but not exposed in the main component interface
+#ifndef OTA_ABORT
+#define OTA_ABORT 3
+#define OTA_ERROR 4
+#endif
+
 #ifdef USE_OTA_STATE_CALLBACK
 #include "esphome/core/automation.h"
 #endif
@@ -11,43 +20,6 @@
 namespace esphome {
 namespace ota {
 
-enum OTAResponseTypes {
-  OTA_RESPONSE_OK = 0x00,
-  OTA_RESPONSE_REQUEST_AUTH = 0x01,
-
-  OTA_RESPONSE_HEADER_OK = 0x40,
-  OTA_RESPONSE_AUTH_OK = 0x41,
-  OTA_RESPONSE_UPDATE_PREPARE_OK = 0x42,
-  OTA_RESPONSE_BIN_MD5_OK = 0x43,
-  OTA_RESPONSE_RECEIVE_OK = 0x44,
-  OTA_RESPONSE_UPDATE_END_OK = 0x45,
-  OTA_RESPONSE_SUPPORTS_COMPRESSION = 0x46,
-  OTA_RESPONSE_CHUNK_OK = 0x47,
-
-  OTA_RESPONSE_ERROR_MAGIC = 0x80,
-  OTA_RESPONSE_ERROR_UPDATE_PREPARE = 0x81,
-  OTA_RESPONSE_ERROR_AUTH_INVALID = 0x82,
-  OTA_RESPONSE_ERROR_WRITING_FLASH = 0x83,
-  OTA_RESPONSE_ERROR_UPDATE_END = 0x84,
-  OTA_RESPONSE_ERROR_INVALID_BOOTSTRAPPING = 0x85,
-  OTA_RESPONSE_ERROR_WRONG_CURRENT_FLASH_CONFIG = 0x86,
-  OTA_RESPONSE_ERROR_WRONG_NEW_FLASH_CONFIG = 0x87,
-  OTA_RESPONSE_ERROR_ESP8266_NOT_ENOUGH_SPACE = 0x88,
-  OTA_RESPONSE_ERROR_ESP32_NOT_ENOUGH_SPACE = 0x89,
-  OTA_RESPONSE_ERROR_NO_UPDATE_PARTITION = 0x8A,
-  OTA_RESPONSE_ERROR_MD5_MISMATCH = 0x8B,
-  OTA_RESPONSE_ERROR_RP2040_NOT_ENOUGH_SPACE = 0x8C,
-  OTA_RESPONSE_ERROR_UNKNOWN = 0xFF,
-};
-
-enum OTAState {
-  OTA_COMPLETED = 0,
-  OTA_STARTED,
-  OTA_IN_PROGRESS,
-  OTA_ABORT,
-  OTA_ERROR,
-};
-
 class OTABackend {
  public:
   virtual ~OTABackend() = default;
@@ -59,18 +31,6 @@ class OTABackend {
   virtual bool supports_compression() = 0;
 };
 
-class OTAComponent : public Component {
-#ifdef USE_OTA_STATE_CALLBACK
- public:
-  void add_on_state_callback(std::function<void(ota::OTAState, float, uint8_t)> &&callback) {
-    this->state_callback_.add(std::move(callback));
-  }
-
- protected:
-  CallbackManager<void(ota::OTAState, float, uint8_t)> state_callback_{};
-#endif
-};
-
 #ifdef USE_OTA_STATE_CALLBACK
 class OTAGlobalCallback {
  public:
@@ -90,7 +50,8 @@ class OTAGlobalCallback {
 OTAGlobalCallback *get_global_ota_callback();
 void register_ota_platform(OTAComponent *ota_caller);
 #endif
-std::unique_ptr<ota::OTABackend> make_ota_backend();
+// This function is defined in ota_component.cpp
+std::unique_ptr<OTABackend> make_ota_backend();
 
 }  // namespace ota
 }  // namespace esphome
diff --git a/esphome/components/ota/ota_backend_arduino_esp32.cpp b/esphome/components/ota/ota_backend_arduino_esp32.cpp
index 15dfc98a6c..983cd77f21 100644
--- a/esphome/components/ota/ota_backend_arduino_esp32.cpp
+++ b/esphome/components/ota/ota_backend_arduino_esp32.cpp
@@ -12,7 +12,7 @@ namespace ota {
 
 static const char *const TAG = "ota.arduino_esp32";
 
-std::unique_ptr<ota::OTABackend> make_ota_backend() { return make_unique<ota::ArduinoESP32OTABackend>(); }
+// Function is now defined in ota_component.cpp
 
 OTAResponseTypes ArduinoESP32OTABackend::begin(size_t image_size) {
   bool ret = Update.begin(image_size, U_FLASH);
diff --git a/esphome/components/ota/ota_backend_arduino_esp8266.cpp b/esphome/components/ota/ota_backend_arduino_esp8266.cpp
index 42edbf5d2b..1039e2a08b 100644
--- a/esphome/components/ota/ota_backend_arduino_esp8266.cpp
+++ b/esphome/components/ota/ota_backend_arduino_esp8266.cpp
@@ -14,7 +14,7 @@ namespace ota {
 
 static const char *const TAG = "ota.arduino_esp8266";
 
-std::unique_ptr<ota::OTABackend> make_ota_backend() { return make_unique<ota::ArduinoESP8266OTABackend>(); }
+// Function is now defined in ota_component.cpp
 
 OTAResponseTypes ArduinoESP8266OTABackend::begin(size_t image_size) {
   bool ret = Update.begin(image_size, U_FLASH);
diff --git a/esphome/components/ota/ota_backend_arduino_libretiny.cpp b/esphome/components/ota/ota_backend_arduino_libretiny.cpp
index 6b2cf80684..7967f018e6 100644
--- a/esphome/components/ota/ota_backend_arduino_libretiny.cpp
+++ b/esphome/components/ota/ota_backend_arduino_libretiny.cpp
@@ -12,7 +12,7 @@ namespace ota {
 
 static const char *const TAG = "ota.arduino_libretiny";
 
-std::unique_ptr<ota::OTABackend> make_ota_backend() { return make_unique<ota::ArduinoLibreTinyOTABackend>(); }
+// Function is now defined in ota_component.cpp
 
 OTAResponseTypes ArduinoLibreTinyOTABackend::begin(size_t image_size) {
   bool ret = Update.begin(image_size, U_FLASH);
diff --git a/esphome/components/ota/ota_backend_arduino_rp2040.cpp b/esphome/components/ota/ota_backend_arduino_rp2040.cpp
index ffeab2e93f..e469e4f3cb 100644
--- a/esphome/components/ota/ota_backend_arduino_rp2040.cpp
+++ b/esphome/components/ota/ota_backend_arduino_rp2040.cpp
@@ -14,7 +14,7 @@ namespace ota {
 
 static const char *const TAG = "ota.arduino_rp2040";
 
-std::unique_ptr<ota::OTABackend> make_ota_backend() { return make_unique<ota::ArduinoRP2040OTABackend>(); }
+// Function is now defined in ota_component.cpp
 
 OTAResponseTypes ArduinoRP2040OTABackend::begin(size_t image_size) {
   bool ret = Update.begin(image_size, U_FLASH);
diff --git a/esphome/components/ota/ota_backend_esp_idf.cpp b/esphome/components/ota/ota_backend_esp_idf.cpp
index 6f45fb75e4..fb46c555c6 100644
--- a/esphome/components/ota/ota_backend_esp_idf.cpp
+++ b/esphome/components/ota/ota_backend_esp_idf.cpp
@@ -14,7 +14,7 @@
 namespace esphome {
 namespace ota {
 
-std::unique_ptr<ota::OTABackend> make_ota_backend() { return make_unique<ota::IDFOTABackend>(); }
+// Function is now defined in ota_component.cpp
 
 OTAResponseTypes IDFOTABackend::begin(size_t image_size) {
   this->partition_ = esp_ota_get_next_update_partition(nullptr);