diff --git a/tests/unit_tests/conftest.py b/tests/unit_tests/conftest.py
index aac5a642f6..a1e438b577 100644
--- a/tests/unit_tests/conftest.py
+++ b/tests/unit_tests/conftest.py
@@ -36,3 +36,10 @@ def fixture_path() -> Path:
     Location of all fixture files.
     """
     return here / "fixtures"
+
+
+@pytest.fixture
+def setup_core(tmp_path: Path) -> Path:
+    """Set up CORE with test paths."""
+    CORE.config_path = str(tmp_path / "test.yaml")
+    return tmp_path
diff --git a/tests/unit_tests/test_config_validation_paths.py b/tests/unit_tests/test_config_validation_paths.py
new file mode 100644
index 0000000000..f8f038390e
--- /dev/null
+++ b/tests/unit_tests/test_config_validation_paths.py
@@ -0,0 +1,187 @@
+"""Tests for config_validation.py path-related functions."""
+
+from pathlib import Path
+
+import pytest
+import voluptuous as vol
+
+from esphome import config_validation as cv
+
+
+def test_directory_valid_path(setup_core: Path) -> None:
+    """Test directory validator with valid directory."""
+    test_dir = setup_core / "test_directory"
+    test_dir.mkdir()
+
+    result = cv.directory("test_directory")
+
+    assert result == "test_directory"
+
+
+def test_directory_absolute_path(setup_core: Path) -> None:
+    """Test directory validator with absolute path."""
+    test_dir = setup_core / "test_directory"
+    test_dir.mkdir()
+
+    result = cv.directory(str(test_dir))
+
+    assert result == str(test_dir)
+
+
+def test_directory_nonexistent_path(setup_core: Path) -> None:
+    """Test directory validator raises error for non-existent directory."""
+    with pytest.raises(
+        vol.Invalid, match="Could not find directory.*nonexistent_directory"
+    ):
+        cv.directory("nonexistent_directory")
+
+
+def test_directory_file_instead_of_directory(setup_core: Path) -> None:
+    """Test directory validator raises error when path is a file."""
+    test_file = setup_core / "test_file.txt"
+    test_file.write_text("content")
+
+    with pytest.raises(vol.Invalid, match="is not a directory"):
+        cv.directory("test_file.txt")
+
+
+def test_directory_with_parent_directory(setup_core: Path) -> None:
+    """Test directory validator with nested directory structure."""
+    nested_dir = setup_core / "parent" / "child" / "grandchild"
+    nested_dir.mkdir(parents=True)
+
+    result = cv.directory("parent/child/grandchild")
+
+    assert result == "parent/child/grandchild"
+
+
+def test_file_valid_path(setup_core: Path) -> None:
+    """Test file_ validator with valid file."""
+    test_file = setup_core / "test_file.yaml"
+    test_file.write_text("test content")
+
+    result = cv.file_("test_file.yaml")
+
+    assert result == "test_file.yaml"
+
+
+def test_file_absolute_path(setup_core: Path) -> None:
+    """Test file_ validator with absolute path."""
+    test_file = setup_core / "test_file.yaml"
+    test_file.write_text("test content")
+
+    result = cv.file_(str(test_file))
+
+    assert result == str(test_file)
+
+
+def test_file_nonexistent_path(setup_core: Path) -> None:
+    """Test file_ validator raises error for non-existent file."""
+    with pytest.raises(vol.Invalid, match="Could not find file.*nonexistent_file.yaml"):
+        cv.file_("nonexistent_file.yaml")
+
+
+def test_file_directory_instead_of_file(setup_core: Path) -> None:
+    """Test file_ validator raises error when path is a directory."""
+    test_dir = setup_core / "test_directory"
+    test_dir.mkdir()
+
+    with pytest.raises(vol.Invalid, match="is not a file"):
+        cv.file_("test_directory")
+
+
+def test_file_with_parent_directory(setup_core: Path) -> None:
+    """Test file_ validator with file in nested directory."""
+    nested_dir = setup_core / "configs" / "sensors"
+    nested_dir.mkdir(parents=True)
+    test_file = nested_dir / "temperature.yaml"
+    test_file.write_text("sensor config")
+
+    result = cv.file_("configs/sensors/temperature.yaml")
+
+    assert result == "configs/sensors/temperature.yaml"
+
+
+def test_directory_handles_trailing_slash(setup_core: Path) -> None:
+    """Test directory validator handles trailing slashes correctly."""
+    test_dir = setup_core / "test_dir"
+    test_dir.mkdir()
+
+    result = cv.directory("test_dir/")
+    assert result == "test_dir/"
+
+    result = cv.directory("test_dir")
+    assert result == "test_dir"
+
+
+def test_file_handles_various_extensions(setup_core: Path) -> None:
+    """Test file_ validator works with different file extensions."""
+    yaml_file = setup_core / "config.yaml"
+    yaml_file.write_text("yaml content")
+    assert cv.file_("config.yaml") == "config.yaml"
+
+    yml_file = setup_core / "config.yml"
+    yml_file.write_text("yml content")
+    assert cv.file_("config.yml") == "config.yml"
+
+    txt_file = setup_core / "readme.txt"
+    txt_file.write_text("text content")
+    assert cv.file_("readme.txt") == "readme.txt"
+
+    no_ext_file = setup_core / "LICENSE"
+    no_ext_file.write_text("license content")
+    assert cv.file_("LICENSE") == "LICENSE"
+
+
+def test_directory_with_symlink(setup_core: Path) -> None:
+    """Test directory validator follows symlinks."""
+    actual_dir = setup_core / "actual_directory"
+    actual_dir.mkdir()
+
+    symlink_dir = setup_core / "symlink_directory"
+    symlink_dir.symlink_to(actual_dir)
+
+    result = cv.directory("symlink_directory")
+    assert result == "symlink_directory"
+
+
+def test_file_with_symlink(setup_core: Path) -> None:
+    """Test file_ validator follows symlinks."""
+    actual_file = setup_core / "actual_file.txt"
+    actual_file.write_text("content")
+
+    symlink_file = setup_core / "symlink_file.txt"
+    symlink_file.symlink_to(actual_file)
+
+    result = cv.file_("symlink_file.txt")
+    assert result == "symlink_file.txt"
+
+
+def test_directory_error_shows_full_path(setup_core: Path) -> None:
+    """Test directory validator error message includes full path."""
+    with pytest.raises(vol.Invalid, match=".*missing_dir.*full path:.*"):
+        cv.directory("missing_dir")
+
+
+def test_file_error_shows_full_path(setup_core: Path) -> None:
+    """Test file_ validator error message includes full path."""
+    with pytest.raises(vol.Invalid, match=".*missing_file.yaml.*full path:.*"):
+        cv.file_("missing_file.yaml")
+
+
+def test_directory_with_spaces_in_name(setup_core: Path) -> None:
+    """Test directory validator handles spaces in directory names."""
+    dir_with_spaces = setup_core / "my test directory"
+    dir_with_spaces.mkdir()
+
+    result = cv.directory("my test directory")
+    assert result == "my test directory"
+
+
+def test_file_with_spaces_in_name(setup_core: Path) -> None:
+    """Test file_ validator handles spaces in file names."""
+    file_with_spaces = setup_core / "my test file.yaml"
+    file_with_spaces.write_text("content")
+
+    result = cv.file_("my test file.yaml")
+    assert result == "my test file.yaml"
diff --git a/tests/unit_tests/test_external_files.py b/tests/unit_tests/test_external_files.py
new file mode 100644
index 0000000000..3fa7de2f64
--- /dev/null
+++ b/tests/unit_tests/test_external_files.py
@@ -0,0 +1,196 @@
+"""Tests for external_files.py functions."""
+
+from pathlib import Path
+import time
+from unittest.mock import MagicMock, patch
+
+import pytest
+import requests
+
+from esphome import external_files
+from esphome.config_validation import Invalid
+from esphome.core import CORE, TimePeriod
+
+
+def test_compute_local_file_dir(setup_core: Path) -> None:
+    """Test compute_local_file_dir creates and returns correct path."""
+    domain = "font"
+
+    result = external_files.compute_local_file_dir(domain)
+
+    assert isinstance(result, Path)
+    assert result == Path(CORE.data_dir) / domain
+    assert result.exists()
+    assert result.is_dir()
+
+
+def test_compute_local_file_dir_nested(setup_core: Path) -> None:
+    """Test compute_local_file_dir works with nested domains."""
+    domain = "images/icons"
+
+    result = external_files.compute_local_file_dir(domain)
+
+    assert result == Path(CORE.data_dir) / "images" / "icons"
+    assert result.exists()
+    assert result.is_dir()
+
+
+def test_is_file_recent_with_recent_file(setup_core: Path) -> None:
+    """Test is_file_recent returns True for recently created file."""
+    test_file = setup_core / "recent.txt"
+    test_file.write_text("content")
+
+    refresh = TimePeriod(seconds=3600)
+
+    result = external_files.is_file_recent(str(test_file), refresh)
+
+    assert result is True
+
+
+def test_is_file_recent_with_old_file(setup_core: Path) -> None:
+    """Test is_file_recent returns False for old file."""
+    test_file = setup_core / "old.txt"
+    test_file.write_text("content")
+
+    old_time = time.time() - 7200
+
+    with patch("os.path.getctime", return_value=old_time):
+        refresh = TimePeriod(seconds=3600)
+
+        result = external_files.is_file_recent(str(test_file), refresh)
+
+        assert result is False
+
+
+def test_is_file_recent_nonexistent_file(setup_core: Path) -> None:
+    """Test is_file_recent returns False for non-existent file."""
+    test_file = setup_core / "nonexistent.txt"
+    refresh = TimePeriod(seconds=3600)
+
+    result = external_files.is_file_recent(str(test_file), refresh)
+
+    assert result is False
+
+
+def test_is_file_recent_with_zero_refresh(setup_core: Path) -> None:
+    """Test is_file_recent with zero refresh period returns False."""
+    test_file = setup_core / "test.txt"
+    test_file.write_text("content")
+
+    # Mock getctime to return a time 10 seconds ago
+    with patch("os.path.getctime", return_value=time.time() - 10):
+        refresh = TimePeriod(seconds=0)
+        result = external_files.is_file_recent(str(test_file), refresh)
+        assert result is False
+
+
+@patch("esphome.external_files.requests.head")
+def test_has_remote_file_changed_not_modified(
+    mock_head: MagicMock, setup_core: Path
+) -> None:
+    """Test has_remote_file_changed returns False when file not modified."""
+    test_file = setup_core / "cached.txt"
+    test_file.write_text("cached content")
+
+    mock_response = MagicMock()
+    mock_response.status_code = 304
+    mock_head.return_value = mock_response
+
+    url = "https://example.com/file.txt"
+    result = external_files.has_remote_file_changed(url, str(test_file))
+
+    assert result is False
+    mock_head.assert_called_once()
+
+    call_args = mock_head.call_args
+    headers = call_args[1]["headers"]
+    assert external_files.IF_MODIFIED_SINCE in headers
+    assert external_files.CACHE_CONTROL in headers
+
+
+@patch("esphome.external_files.requests.head")
+def test_has_remote_file_changed_modified(
+    mock_head: MagicMock, setup_core: Path
+) -> None:
+    """Test has_remote_file_changed returns True when file modified."""
+    test_file = setup_core / "cached.txt"
+    test_file.write_text("cached content")
+
+    mock_response = MagicMock()
+    mock_response.status_code = 200
+    mock_head.return_value = mock_response
+
+    url = "https://example.com/file.txt"
+    result = external_files.has_remote_file_changed(url, str(test_file))
+
+    assert result is True
+
+
+def test_has_remote_file_changed_no_local_file(setup_core: Path) -> None:
+    """Test has_remote_file_changed returns True when local file doesn't exist."""
+    test_file = setup_core / "nonexistent.txt"
+
+    url = "https://example.com/file.txt"
+    result = external_files.has_remote_file_changed(url, str(test_file))
+
+    assert result is True
+
+
+@patch("esphome.external_files.requests.head")
+def test_has_remote_file_changed_network_error(
+    mock_head: MagicMock, setup_core: Path
+) -> None:
+    """Test has_remote_file_changed handles network errors gracefully."""
+    test_file = setup_core / "cached.txt"
+    test_file.write_text("cached content")
+
+    mock_head.side_effect = requests.exceptions.RequestException("Network error")
+
+    url = "https://example.com/file.txt"
+
+    with pytest.raises(Invalid, match="Could not check if.*Network error"):
+        external_files.has_remote_file_changed(url, str(test_file))
+
+
+@patch("esphome.external_files.requests.head")
+def test_has_remote_file_changed_timeout(
+    mock_head: MagicMock, setup_core: Path
+) -> None:
+    """Test has_remote_file_changed respects timeout."""
+    test_file = setup_core / "cached.txt"
+    test_file.write_text("cached content")
+
+    mock_response = MagicMock()
+    mock_response.status_code = 304
+    mock_head.return_value = mock_response
+
+    url = "https://example.com/file.txt"
+    external_files.has_remote_file_changed(url, str(test_file))
+
+    call_args = mock_head.call_args
+    assert call_args[1]["timeout"] == external_files.NETWORK_TIMEOUT
+
+
+def test_compute_local_file_dir_creates_parent_dirs(setup_core: Path) -> None:
+    """Test compute_local_file_dir creates parent directories."""
+    domain = "level1/level2/level3/level4"
+
+    result = external_files.compute_local_file_dir(domain)
+
+    assert result.exists()
+    assert result.is_dir()
+    assert result.parent.name == "level3"
+    assert result.parent.parent.name == "level2"
+    assert result.parent.parent.parent.name == "level1"
+
+
+def test_is_file_recent_handles_float_seconds(setup_core: Path) -> None:
+    """Test is_file_recent works with float seconds in TimePeriod."""
+    test_file = setup_core / "test.txt"
+    test_file.write_text("content")
+
+    refresh = TimePeriod(seconds=3600.5)
+
+    result = external_files.is_file_recent(str(test_file), refresh)
+
+    assert result is True
diff --git a/tests/unit_tests/test_platformio_api.py b/tests/unit_tests/test_platformio_api.py
new file mode 100644
index 0000000000..a1fa963e51
--- /dev/null
+++ b/tests/unit_tests/test_platformio_api.py
@@ -0,0 +1,129 @@
+"""Tests for platformio_api.py path functions."""
+
+from pathlib import Path
+from unittest.mock import patch
+
+from esphome import platformio_api
+from esphome.core import CORE
+
+
+def test_idedata_firmware_elf_path(setup_core: Path) -> None:
+    """Test IDEData.firmware_elf_path returns correct path."""
+    CORE.build_path = str(setup_core / "build" / "test")
+    CORE.name = "test"
+    raw_data = {"prog_path": "/path/to/firmware.elf"}
+    idedata = platformio_api.IDEData(raw_data)
+
+    assert idedata.firmware_elf_path == "/path/to/firmware.elf"
+
+
+def test_idedata_firmware_bin_path(setup_core: Path) -> None:
+    """Test IDEData.firmware_bin_path returns Path with .bin extension."""
+    CORE.build_path = str(setup_core / "build" / "test")
+    CORE.name = "test"
+    prog_path = str(Path("/path/to/firmware.elf"))
+    raw_data = {"prog_path": prog_path}
+    idedata = platformio_api.IDEData(raw_data)
+
+    result = idedata.firmware_bin_path
+    assert isinstance(result, str)
+    expected = str(Path("/path/to/firmware.bin"))
+    assert result == expected
+    assert result.endswith(".bin")
+
+
+def test_idedata_firmware_bin_path_preserves_directory(setup_core: Path) -> None:
+    """Test firmware_bin_path preserves the directory structure."""
+    CORE.build_path = str(setup_core / "build" / "test")
+    CORE.name = "test"
+    prog_path = str(Path("/complex/path/to/build/firmware.elf"))
+    raw_data = {"prog_path": prog_path}
+    idedata = platformio_api.IDEData(raw_data)
+
+    result = idedata.firmware_bin_path
+    expected = str(Path("/complex/path/to/build/firmware.bin"))
+    assert result == expected
+
+
+def test_idedata_extra_flash_images(setup_core: Path) -> None:
+    """Test IDEData.extra_flash_images returns list of FlashImage objects."""
+    CORE.build_path = str(setup_core / "build" / "test")
+    CORE.name = "test"
+    raw_data = {
+        "prog_path": "/path/to/firmware.elf",
+        "extra": {
+            "flash_images": [
+                {"path": "/path/to/bootloader.bin", "offset": "0x1000"},
+                {"path": "/path/to/partition.bin", "offset": "0x8000"},
+            ]
+        },
+    }
+    idedata = platformio_api.IDEData(raw_data)
+
+    images = idedata.extra_flash_images
+    assert len(images) == 2
+    assert all(isinstance(img, platformio_api.FlashImage) for img in images)
+    assert images[0].path == "/path/to/bootloader.bin"
+    assert images[0].offset == "0x1000"
+    assert images[1].path == "/path/to/partition.bin"
+    assert images[1].offset == "0x8000"
+
+
+def test_idedata_extra_flash_images_empty(setup_core: Path) -> None:
+    """Test extra_flash_images returns empty list when no extra images."""
+    CORE.build_path = str(setup_core / "build" / "test")
+    CORE.name = "test"
+    raw_data = {"prog_path": "/path/to/firmware.elf", "extra": {"flash_images": []}}
+    idedata = platformio_api.IDEData(raw_data)
+
+    images = idedata.extra_flash_images
+    assert images == []
+
+
+def test_idedata_cc_path(setup_core: Path) -> None:
+    """Test IDEData.cc_path returns compiler path."""
+    CORE.build_path = str(setup_core / "build" / "test")
+    CORE.name = "test"
+    raw_data = {
+        "prog_path": "/path/to/firmware.elf",
+        "cc_path": "/Users/test/.platformio/packages/toolchain-xtensa32/bin/xtensa-esp32-elf-gcc",
+    }
+    idedata = platformio_api.IDEData(raw_data)
+
+    assert (
+        idedata.cc_path
+        == "/Users/test/.platformio/packages/toolchain-xtensa32/bin/xtensa-esp32-elf-gcc"
+    )
+
+
+def test_flash_image_dataclass() -> None:
+    """Test FlashImage dataclass stores path and offset correctly."""
+    image = platformio_api.FlashImage(path="/path/to/image.bin", offset="0x10000")
+
+    assert image.path == "/path/to/image.bin"
+    assert image.offset == "0x10000"
+
+
+def test_load_idedata_returns_dict(setup_core: Path) -> None:
+    """Test _load_idedata returns parsed idedata dict when successful."""
+    CORE.build_path = str(setup_core / "build" / "test")
+    CORE.name = "test"
+
+    # Create required files
+    platformio_ini = setup_core / "build" / "test" / "platformio.ini"
+    platformio_ini.parent.mkdir(parents=True, exist_ok=True)
+    platformio_ini.touch()
+
+    idedata_path = setup_core / ".esphome" / "idedata" / "test.json"
+    idedata_path.parent.mkdir(parents=True, exist_ok=True)
+    idedata_path.write_text('{"prog_path": "/test/firmware.elf"}')
+
+    with patch("esphome.platformio_api.run_platformio_cli_run") as mock_run:
+        mock_run.return_value = '{"prog_path": "/test/firmware.elf"}'
+
+        config = {"name": "test"}
+        result = platformio_api._load_idedata(config)
+
+    assert result is not None
+    assert isinstance(result, dict)
+    assert result["prog_path"] == "/test/firmware.elf"
diff --git a/tests/unit_tests/test_storage_json.py b/tests/unit_tests/test_storage_json.py
new file mode 100644
index 0000000000..52de327bbc
--- /dev/null
+++ b/tests/unit_tests/test_storage_json.py
@@ -0,0 +1,182 @@
+"""Tests for storage_json.py path functions."""
+
+from pathlib import Path
+import sys
+from unittest.mock import patch
+
+import pytest
+
+from esphome import storage_json
+from esphome.core import CORE
+
+
+def test_storage_path(setup_core: Path) -> None:
+    """Test storage_path returns correct path for current config."""
+    CORE.config_path = str(setup_core / "my_device.yaml")
+
+    result = storage_json.storage_path()
+
+    data_dir = Path(CORE.data_dir)
+    expected = str(data_dir / "storage" / "my_device.yaml.json")
+    assert result == expected
+
+
+def test_ext_storage_path(setup_core: Path) -> None:
+    """Test ext_storage_path returns correct path for given filename."""
+    result = storage_json.ext_storage_path("other_device.yaml")
+
+    data_dir = Path(CORE.data_dir)
+    expected = str(data_dir / "storage" / "other_device.yaml.json")
+    assert result == expected
+
+
+def test_ext_storage_path_handles_various_extensions(setup_core: Path) -> None:
+    """Test ext_storage_path works with different file extensions."""
+    result_yml = storage_json.ext_storage_path("device.yml")
+    assert result_yml.endswith("device.yml.json")
+
+    result_no_ext = storage_json.ext_storage_path("device")
+    assert result_no_ext.endswith("device.json")
+
+    result_path = storage_json.ext_storage_path("my/device.yaml")
+    assert result_path.endswith("device.yaml.json")
+
+
+def test_esphome_storage_path(setup_core: Path) -> None:
+    """Test esphome_storage_path returns correct path."""
+    result = storage_json.esphome_storage_path()
+
+    data_dir = Path(CORE.data_dir)
+    expected = str(data_dir / "esphome.json")
+    assert result == expected
+
+
+def test_ignored_devices_storage_path(setup_core: Path) -> None:
+    """Test ignored_devices_storage_path returns correct path."""
+    result = storage_json.ignored_devices_storage_path()
+
+    data_dir = Path(CORE.data_dir)
+    expected = str(data_dir / "ignored-devices.json")
+    assert result == expected
+
+
+def test_trash_storage_path(setup_core: Path) -> None:
+    """Test trash_storage_path returns correct path."""
+    CORE.config_path = str(setup_core / "configs" / "device.yaml")
+
+    result = storage_json.trash_storage_path()
+
+    expected = str(setup_core / "configs" / "trash")
+    assert result == expected
+
+
+def test_archive_storage_path(setup_core: Path) -> None:
+    """Test archive_storage_path returns correct path."""
+    CORE.config_path = str(setup_core / "configs" / "device.yaml")
+
+    result = storage_json.archive_storage_path()
+
+    expected = str(setup_core / "configs" / "archive")
+    assert result == expected
+
+
+def test_storage_path_with_subdirectory(setup_core: Path) -> None:
+    """Test storage paths work correctly when config is in subdirectory."""
+    subdir = setup_core / "configs" / "basement"
+    subdir.mkdir(parents=True, exist_ok=True)
+    CORE.config_path = str(subdir / "sensor.yaml")
+
+    result = storage_json.storage_path()
+
+    data_dir = Path(CORE.data_dir)
+    expected = str(data_dir / "storage" / "sensor.yaml.json")
+    assert result == expected
+
+
+def test_storage_json_firmware_bin_path_property(setup_core: Path) -> None:
+    """Test StorageJSON firmware_bin_path property."""
+    storage = storage_json.StorageJSON(
+        storage_version=1,
+        name="test_device",
+        friendly_name="Test Device",
+        comment=None,
+        esphome_version="2024.1.0",
+        src_version=None,
+        address="192.168.1.100",
+        web_port=80,
+        target_platform="ESP32",
+        build_path="build/test_device",
+        firmware_bin_path="/path/to/firmware.bin",
+        loaded_integrations={"wifi", "api"},
+        loaded_platforms=set(),
+        no_mdns=False,
+    )
+
+    assert storage.firmware_bin_path == "/path/to/firmware.bin"
+
+
+def test_storage_json_save_creates_directory(setup_core: Path, tmp_path: Path) -> None:
+    """Test StorageJSON.save creates storage directory if it doesn't exist."""
+    storage_dir = tmp_path / "new_data" / "storage"
+    storage_file = storage_dir / "test.json"
+
+    assert not storage_dir.exists()
+
+    storage = storage_json.StorageJSON(
+        storage_version=1,
+        name="test",
+        friendly_name="Test",
+        comment=None,
+        esphome_version="2024.1.0",
+        src_version=None,
+        address="test.local",
+        web_port=None,
+        target_platform="ESP8266",
+        build_path=None,
+        firmware_bin_path=None,
+        loaded_integrations=set(),
+        loaded_platforms=set(),
+        no_mdns=False,
+    )
+
+    with patch("esphome.storage_json.write_file_if_changed") as mock_write:
+        storage.save(str(storage_file))
+        mock_write.assert_called_once()
+        call_args = mock_write.call_args[0]
+        assert call_args[0] == str(storage_file)
+
+
+def test_storage_json_from_wizard(setup_core: Path) -> None:
+    """Test StorageJSON.from_wizard creates correct storage object."""
+    storage = storage_json.StorageJSON.from_wizard(
+        name="my_device",
+        friendly_name="My Device",
+        address="my_device.local",
+        platform="ESP32",
+    )
+
+    assert storage.name == "my_device"
+    assert storage.friendly_name == "My Device"
+    assert storage.address == "my_device.local"
+    assert storage.target_platform == "ESP32"
+    assert storage.build_path is None
+    assert storage.firmware_bin_path is None
+
+
+@pytest.mark.skipif(sys.platform == "win32", reason="HA addons don't run on Windows")
+@patch("esphome.core.is_ha_addon")
+def test_storage_paths_with_ha_addon(mock_is_ha_addon: bool, tmp_path: Path) -> None:
+    """Test storage paths when running as Home Assistant addon."""
+    mock_is_ha_addon.return_value = True
+
+    CORE.config_path = str(tmp_path / "test.yaml")
+
+    result = storage_json.storage_path()
+    # When is_ha_addon is True, CORE.data_dir returns "/data"
+    # This is the standard mount point for HA addon containers
+    expected = str(Path("/data") / "storage" / "test.yaml.json")
+    assert result == expected
+
+    result = storage_json.esphome_storage_path()
+    expected = str(Path("/data") / "esphome.json")
+    assert result == expected