diff --git a/tests/unit_tests/test_writer.py b/tests/unit_tests/test_writer.py
index f354d71bb73..c792f09f795 100644
--- a/tests/unit_tests/test_writer.py
+++ b/tests/unit_tests/test_writer.py
@@ -28,6 +28,7 @@ from esphome.writer import (
     generate_build_info_data_h,
     get_build_info,
     storage_should_clean,
+    storage_should_update_cmake_cache,
     update_storage_json,
     write_cpp,
     write_gitignore,
@@ -171,6 +172,113 @@ def test_storage_edge_case_from_empty_integrations(
     assert storage_should_clean(old, new) is False
 
 
+# Tests for storage_should_update_cmake_cache
+
+
+def test_storage_should_update_cmake_cache_when_integration_added_esp32(
+    create_storage: Callable[..., StorageJSON],
+) -> None:
+    """Test cmake cache update triggered when integration added on ESP32."""
+    old = create_storage(
+        loaded_integrations=["api", "wifi"],
+        core_platform="esp32",
+        framework="arduino",
+    )
+    new = create_storage(
+        loaded_integrations=["api", "wifi", "restart"],
+        core_platform="esp32",
+        framework="arduino",
+    )
+    assert storage_should_update_cmake_cache(old, new) is True
+
+
+def test_storage_should_update_cmake_cache_when_integration_added_esp32_idf(
+    create_storage: Callable[..., StorageJSON],
+) -> None:
+    """Test cmake cache update triggered when integration added on ESP32-IDF."""
+    old = create_storage(
+        loaded_integrations=["api", "wifi"],
+        core_platform="esp32",
+        framework="esp-idf",
+    )
+    new = create_storage(
+        loaded_integrations=["api", "wifi", "restart"],
+        core_platform="esp32",
+        framework="esp-idf",
+    )
+    assert storage_should_update_cmake_cache(old, new) is True
+
+
+def test_storage_should_update_cmake_cache_when_platform_changed_esp32(
+    create_storage: Callable[..., StorageJSON],
+) -> None:
+    """Test cmake cache update triggered when platforms change on ESP32."""
+    old = create_storage(
+        loaded_integrations=["api", "wifi"],
+        loaded_platforms={"sensor"},
+        core_platform="esp32",
+        framework="arduino",
+    )
+    new = create_storage(
+        loaded_integrations=["api", "wifi"],
+        loaded_platforms={"sensor", "binary_sensor"},
+        core_platform="esp32",
+        framework="arduino",
+    )
+    assert storage_should_update_cmake_cache(old, new) is True
+
+
+def test_storage_should_not_update_cmake_cache_when_nothing_changes(
+    create_storage: Callable[..., StorageJSON],
+) -> None:
+    """Test cmake cache not updated when nothing changes."""
+    old = create_storage(
+        loaded_integrations=["api", "wifi"],
+        core_platform="esp32",
+        framework="arduino",
+    )
+    new = create_storage(
+        loaded_integrations=["api", "wifi"],
+        core_platform="esp32",
+        framework="arduino",
+    )
+    assert storage_should_update_cmake_cache(old, new) is False
+
+
+def test_storage_should_not_update_cmake_cache_for_esp8266(
+    create_storage: Callable[..., StorageJSON],
+) -> None:
+    """Test cmake cache not updated for ESP8266 (uses different build system)."""
+    old = create_storage(
+        loaded_integrations=["api", "wifi"],
+        core_platform="esp8266",
+        framework="arduino",
+    )
+    new = create_storage(
+        loaded_integrations=["api", "wifi", "restart"],
+        core_platform="esp8266",
+        framework="arduino",
+    )
+    assert storage_should_update_cmake_cache(old, new) is False
+
+
+def test_storage_should_not_update_cmake_cache_for_rp2040(
+    create_storage: Callable[..., StorageJSON],
+) -> None:
+    """Test cmake cache not updated for RP2040."""
+    old = create_storage(
+        loaded_integrations=["api", "wifi"],
+        core_platform="rp2040",
+        framework="arduino",
+    )
+    new = create_storage(
+        loaded_integrations=["api", "wifi", "restart"],
+        core_platform="rp2040",
+        framework="arduino",
+    )
+    assert storage_should_update_cmake_cache(old, new) is False
+
+
 @patch("esphome.writer.clean_build")
 @patch("esphome.writer.StorageJSON")
 @patch("esphome.writer.storage_path")