diff --git a/script/hassfest/__main__.py b/script/hassfest/__main__.py
index 3e979b1d8ce..6bd7f2cc3b5 100644
--- a/script/hassfest/__main__.py
+++ b/script/hassfest/__main__.py
@@ -21,6 +21,7 @@ from . import (
     docker,
     icons,
     integration_info,
+    integration_type,
     json,
     labs,
     manifest,
@@ -48,6 +49,7 @@ INTEGRATION_PLUGINS = [
     dhcp,
     icons,
     integration_info,
+    integration_type,
     json,
     labs,
     manifest,
diff --git a/script/hassfest/integration_type.py b/script/hassfest/integration_type.py
new file mode 100644
index 00000000000..e1028ae56f7
--- /dev/null
+++ b/script/hassfest/integration_type.py
@@ -0,0 +1,100 @@
+"""Validate integration type is set for config flow integrations."""
+
+from __future__ import annotations
+
+from .model import Config, Integration
+
+# Integrations with config_flow that are missing integration_type.
+# These need to be fixed; do not add new entries to this list.
+MISSING_INTEGRATION_TYPE = {
+    "abode",
+    "acmeda",
+    "adax",
+    "awair",
+    "bluetooth",
+    "bthome",
+    "chacon_dio",
+    "color_extractor",
+    "crownstone",
+    "deako",
+    "dialogflow",
+    "dynalite",
+    "elmax",
+    "emulated_roku",
+    "ezviz",
+    "file",
+    "filesize",
+    "fluss",
+    "flux_led",
+    "folder_watcher",
+    "forked_daapd",
+    "geniushub",
+    "gentex_homelink",
+    "geofency",
+    "govee_light_local",
+    "gpsd",
+    "gpslogger",
+    "gree",
+    "holiday",
+    "homekit",
+    "html5",
+    "ifttt",
+    "influxdb",
+    "ios",
+    "jewish_calendar",
+    "local_calendar",
+    "local_file",
+    "local_ip",
+    "local_todo",
+    "locative",
+    "mcp",
+    "media_extractor",
+    "mill",
+    "mjpeg",
+    "modern_forms",
+    "ness_alarm",
+    "nmap_tracker",
+    "otp",
+    "orvibo",
+    "profiler",
+    "proximity",
+    "rhasspy",
+    "risco",
+    "rpi_power",
+    "scrape",
+    "shopping_list",
+    "sql",
+    "sunweg",
+    "systemmonitor",
+    "tasmota",
+    "traccar",
+    "traccar_server",
+    "upb",
+    "version",
+    "volvooncall",
+    "wemo",
+    "zodiac",
+}
+
+
+def validate(integrations: dict[str, Integration], config: Config) -> None:
+    """Validate that all config flow integrations declare an integration type."""
+    for integration in integrations.values():
+        if not integration.config_flow or not integration.core:
+            continue
+
+        if "integration_type" in integration.manifest:
+            if integration.domain in MISSING_INTEGRATION_TYPE:
+                integration.add_error(
+                    "integration_type",
+                    "Integration has an `integration_type` in the manifest but is still listed in MISSING_INTEGRATION_TYPE",
+                )
+            continue
+
+        if integration.domain in MISSING_INTEGRATION_TYPE:
+            continue
+
+        integration.add_error(
+            "integration_type",
+            "Integration has a config flow but is missing an `integration_type` in the manifest",
+        )
diff --git a/tests/hassfest/test_integration_type.py b/tests/hassfest/test_integration_type.py
new file mode 100644
index 00000000000..1fdfa096412
--- /dev/null
+++ b/tests/hassfest/test_integration_type.py
@@ -0,0 +1,92 @@
+"""Tests for hassfest integration_type."""
+
+import pytest
+
+from script.hassfest import integration_type
+from script.hassfest.model import Config, Integration
+
+from . import get_integration
+
+
+def _get_integration(domain: str, config: Config, manifest_extra: dict) -> Integration:
+    """Helper to create an integration with extra manifest keys."""
+    integration = get_integration(domain, config)
+    integration.manifest.update(manifest_extra)
+    return integration
+
+
+@pytest.mark.usefixtures("mock_core_integration")
+def test_integration_with_config_flow_and_integration_type(config: Config) -> None:
+    """Integration with config_flow and integration_type should pass without errors."""
+    integrations = {
+        "test": _get_integration(
+            "test",
+            config,
+            {"config_flow": True, "integration_type": "device"},
+        )
+    }
+    integration_type.validate(integrations, config)
+    assert integrations["test"].errors == []
+
+
+@pytest.mark.usefixtures("mock_core_integration")
+def test_integration_with_config_flow_missing_integration_type(config: Config) -> None:
+    """Integration with config_flow but no integration_type and not in allowlist should error."""
+    integrations = {
+        "test": _get_integration(
+            "test",
+            config,
+            {"config_flow": True},
+        )
+    }
+    integration_type.validate(integrations, config)
+    assert len(integrations["test"].errors) == 1
+    assert "missing an `integration_type`" in integrations["test"].errors[0].error
+
+
+@pytest.mark.usefixtures("mock_core_integration")
+def test_integration_with_config_flow_in_allowlist(config: Config) -> None:
+    """Integration with config_flow but no integration_type and in allowlist should pass."""
+    domain = next(iter(integration_type.MISSING_INTEGRATION_TYPE))
+    integrations = {
+        domain: _get_integration(
+            domain,
+            config,
+            {"config_flow": True},
+        )
+    }
+    integration_type.validate(integrations, config)
+    assert integrations[domain].errors == []
+
+
+@pytest.mark.usefixtures("mock_core_integration")
+def test_integration_with_integration_type_still_in_allowlist(config: Config) -> None:
+    """Integration with integration_type but still in allowlist should error."""
+    domain = next(iter(integration_type.MISSING_INTEGRATION_TYPE))
+    integrations = {
+        domain: _get_integration(
+            domain,
+            config,
+            {"config_flow": True, "integration_type": "device"},
+        )
+    }
+    integration_type.validate(integrations, config)
+    assert len(integrations[domain].errors) == 1
+    assert (
+        "still listed in MISSING_INTEGRATION_TYPE"
+        in integrations[domain].errors[0].error
+    )
+
+
+@pytest.mark.usefixtures("mock_core_integration")
+def test_integration_without_config_flow_skipped(config: Config) -> None:
+    """Integration without config_flow should be skipped regardless of integration_type."""
+    integrations = {
+        "test": _get_integration(
+            "test",
+            config,
+            {},
+        )
+    }
+    integration_type.validate(integrations, config)
+    assert integrations["test"].errors == []