diff --git a/tests/integration/conftest.py b/tests/integration/conftest.py
index a88d4993a3..a4ae6209f5 100644
--- a/tests/integration/conftest.py
+++ b/tests/integration/conftest.py
@@ -62,7 +62,8 @@ def pytest_configure(config: pytest.Config) -> None:
     config.addinivalue_line(
         "markers",
         "shared_yaml(name): load fixtures/<name>.yaml and compile it in a shared, "
-        "hash-keyed incremental build directory",
+        "hash-keyed incremental build directory. Tests sharing a fixture share one "
+        "device name and thus one host prefs file; do not use restore-backed state",
     )
 
 
diff --git a/tests/integration/fixtures/sensor_filters_batch_window.yaml b/tests/integration/fixtures/sensor_filters_batch_window.yaml
deleted file mode 100644
index 58a254c215..0000000000
--- a/tests/integration/fixtures/sensor_filters_batch_window.yaml
+++ /dev/null
@@ -1,58 +0,0 @@
-esphome:
-  name: test-batch-window-filters
-
-host:
-api:
-  batch_delay: 0ms  # Disable batching to receive all state updates
-logger:
-  level: DEBUG
-
-# Template sensor that we'll use to publish values
-sensor:
-  - platform: template
-    name: "Source Sensor"
-    id: source_sensor
-    accuracy_decimals: 2
-
-  # Batch window filters (window_size == send_every) - use streaming filters
-  - platform: copy
-    source_id: source_sensor
-    name: "Min Sensor"
-    id: min_sensor
-    filters:
-      - min:
-          window_size: 5
-          send_every: 5
-          send_first_at: 1
-
-  - platform: copy
-    source_id: source_sensor
-    name: "Max Sensor"
-    id: max_sensor
-    filters:
-      - max:
-          window_size: 5
-          send_every: 5
-          send_first_at: 1
-
-  - platform: copy
-    source_id: source_sensor
-    name: "Moving Avg Sensor"
-    id: moving_avg_sensor
-    filters:
-      - sliding_window_moving_average:
-          window_size: 5
-          send_every: 5
-          send_first_at: 1
-
-# Button to trigger publishing test values
-button:
-  - platform: template
-    name: "Publish Values Button"
-    id: publish_button
-    on_press:
-      - lambda: |-
-          // Publish 10 values: 1.0, 2.0, ..., 10.0
-          for (int i = 1; i <= 10; i++) {
-            id(source_sensor).publish_state(float(i));
-          }
diff --git a/tests/script/test_helpers.py b/tests/script/test_helpers.py
index 861d11816d..99a795a5c1 100644
--- a/tests/script/test_helpers.py
+++ b/tests/script/test_helpers.py
@@ -2136,6 +2136,20 @@ def test_fixture_map_includes_shared_yaml_markers() -> None:
         )
 
 
+def test_no_orphan_integration_fixtures() -> None:
+    """Every fixture must reach CI test selection; an orphan selects nothing."""
+    helpers.get_fixture_to_test_files.cache_clear()
+    mapping = helpers.get_fixture_to_test_files()
+    fixtures_dir = (Path(__file__).parent.parent / "integration" / "fixtures").resolve()
+    # cache_init is covered via INTEGRATION_TESTS_TRIGGER_FILES instead
+    orphans = [
+        f.stem
+        for f in fixtures_dir.glob("*.yaml")
+        if f.stem != "cache_init" and f.stem not in mapping
+    ]
+    assert not orphans, f"fixtures invisible to CI test selection: {orphans}"
+
+
 def test_lpt_partition_balances_skewed_weights() -> None:
     """Heavy items spread across groups instead of clustering."""
     items = [f"i{n}" for n in range(6)]