diff --git a/homeassistant/components/energy/sensor.py b/homeassistant/components/energy/sensor.py
index 1105e6f6b86..5aa710be19e 100644
--- a/homeassistant/components/energy/sensor.py
+++ b/homeassistant/components/energy/sensor.py
@@ -48,6 +48,7 @@ VALID_ENERGY_UNITS_GAS = {
     UnitOfVolume.CUBIC_FEET,
     UnitOfVolume.CUBIC_METERS,
     UnitOfVolume.LITERS,
+    UnitOfVolume.MILLE_CUBIC_FEET,
     *VALID_ENERGY_UNITS,
 }
 VALID_VOLUME_UNITS_WATER: set[str] = {
@@ -56,6 +57,7 @@ VALID_VOLUME_UNITS_WATER: set[str] = {
     UnitOfVolume.CUBIC_METERS,
     UnitOfVolume.GALLONS,
     UnitOfVolume.LITERS,
+    UnitOfVolume.MILLE_CUBIC_FEET,
 }
 _LOGGER = logging.getLogger(__name__)
 
diff --git a/homeassistant/components/energy/validate.py b/homeassistant/components/energy/validate.py
index 3590ee9e848..6c11c2b068c 100644
--- a/homeassistant/components/energy/validate.py
+++ b/homeassistant/components/energy/validate.py
@@ -42,6 +42,7 @@ GAS_USAGE_UNITS: dict[str, tuple[UnitOfEnergy | UnitOfVolume, ...]] = {
         UnitOfVolume.CUBIC_FEET,
         UnitOfVolume.CUBIC_METERS,
         UnitOfVolume.LITERS,
+        UnitOfVolume.MILLE_CUBIC_FEET,
     ),
 }
 GAS_PRICE_UNITS = tuple(
@@ -57,6 +58,7 @@ WATER_USAGE_UNITS: dict[str, tuple[UnitOfVolume, ...]] = {
         UnitOfVolume.CUBIC_METERS,
         UnitOfVolume.GALLONS,
         UnitOfVolume.LITERS,
+        UnitOfVolume.MILLE_CUBIC_FEET,
     ),
 }
 WATER_PRICE_UNITS = tuple(
diff --git a/homeassistant/components/number/const.py b/homeassistant/components/number/const.py
index 22c1170b6b8..a9333212fa4 100644
--- a/homeassistant/components/number/const.py
+++ b/homeassistant/components/number/const.py
@@ -207,7 +207,7 @@ class NumberDeviceClass(StrEnum):
 
     Unit of measurement:
     - SI / metric: `L`, `m³`
-    - USCS / imperial: `ft³`, `CCF`
+    - USCS / imperial: `ft³`, `CCF`, `MCF`
     """
 
     HUMIDITY = "humidity"
@@ -398,7 +398,7 @@ class NumberDeviceClass(StrEnum):
 
     Unit of measurement: `VOLUME_*` units
     - SI / metric: `mL`, `L`, `m³`
-    - USCS / imperial: `ft³`, `CCF`, `fl. oz.`, `gal` (warning: volumes expressed in
+    - USCS / imperial: `ft³`, `CCF`, `MCF`, `fl. oz.`, `gal` (warning: volumes expressed in
     USCS/imperial units are currently assumed to be US volumes)
     """
 
@@ -410,7 +410,7 @@ class NumberDeviceClass(StrEnum):
 
     Unit of measurement: `VOLUME_*` units
     - SI / metric: `mL`, `L`, `m³`
-    - USCS / imperial: `ft³`, `CCF`, `fl. oz.`, `gal` (warning: volumes expressed in
+    - USCS / imperial: `ft³`, `CCF`, `MCF`, `fl. oz.`, `gal` (warning: volumes expressed in
     USCS/imperial units are currently assumed to be US volumes)
     """
 
@@ -427,7 +427,7 @@ class NumberDeviceClass(StrEnum):
 
     Unit of measurement:
     - SI / metric: `m³`, `L`
-    - USCS / imperial: `ft³`, `CCF`, `gal` (warning: volumes expressed in
+    - USCS / imperial: `ft³`, `CCF`, `MCF`, `gal` (warning: volumes expressed in
     USCS/imperial units are currently assumed to be US volumes)
     """
 
@@ -493,6 +493,7 @@ DEVICE_CLASS_UNITS: dict[NumberDeviceClass, set[type[StrEnum] | str | None]] = {
         UnitOfVolume.CUBIC_FEET,
         UnitOfVolume.CUBIC_METERS,
         UnitOfVolume.LITERS,
+        UnitOfVolume.MILLE_CUBIC_FEET,
     },
     NumberDeviceClass.HUMIDITY: {PERCENTAGE},
     NumberDeviceClass.ILLUMINANCE: {LIGHT_LUX},
@@ -546,6 +547,7 @@ DEVICE_CLASS_UNITS: dict[NumberDeviceClass, set[type[StrEnum] | str | None]] = {
         UnitOfVolume.CUBIC_METERS,
         UnitOfVolume.GALLONS,
         UnitOfVolume.LITERS,
+        UnitOfVolume.MILLE_CUBIC_FEET,
     },
     NumberDeviceClass.WEIGHT: set(UnitOfMass),
     NumberDeviceClass.WIND_DIRECTION: {DEGREE},
diff --git a/homeassistant/components/sensor/const.py b/homeassistant/components/sensor/const.py
index 94578a6f652..12d9595d059 100644
--- a/homeassistant/components/sensor/const.py
+++ b/homeassistant/components/sensor/const.py
@@ -240,7 +240,7 @@ class SensorDeviceClass(StrEnum):
 
     Unit of measurement:
     - SI / metric: `L`, `m³`
-    - USCS / imperial: `ft³`, `CCF`
+    - USCS / imperial: `ft³`, `CCF`, `MCF`
     """
 
     HUMIDITY = "humidity"
@@ -432,7 +432,7 @@ class SensorDeviceClass(StrEnum):
 
     Unit of measurement: `VOLUME_*` units
     - SI / metric: `mL`, `L`, `m³`
-    - USCS / imperial: `ft³`, `CCF`, `fl. oz.`, `gal` (warning: volumes expressed in
+    - USCS / imperial: `ft³`, `CCF`, `MCF`, `fl. oz.`, `gal` (warning: volumes expressed in
     USCS/imperial units are currently assumed to be US volumes)
     """
 
@@ -444,7 +444,7 @@ class SensorDeviceClass(StrEnum):
 
     Unit of measurement: `VOLUME_*` units
     - SI / metric: `mL`, `L`, `m³`
-    - USCS / imperial: `ft³`, `CCF`, `fl. oz.`, `gal` (warning: volumes expressed in
+    - USCS / imperial: `ft³`, `CCF`, `MCF`, `fl. oz.`, `gal` (warning: volumes expressed in
     USCS/imperial units are currently assumed to be US volumes)
     """
 
@@ -461,7 +461,7 @@ class SensorDeviceClass(StrEnum):
 
     Unit of measurement:
     - SI / metric: `m³`, `L`
-    - USCS / imperial: `ft³`, `CCF`, `gal` (warning: volumes expressed in
+    - USCS / imperial: `ft³`, `CCF`, `MCF`, `gal` (warning: volumes expressed in
     USCS/imperial units are currently assumed to be US volumes)
     """
 
@@ -601,6 +601,7 @@ DEVICE_CLASS_UNITS: dict[SensorDeviceClass, set[type[StrEnum] | str | None]] = {
         UnitOfVolume.CUBIC_FEET,
         UnitOfVolume.CUBIC_METERS,
         UnitOfVolume.LITERS,
+        UnitOfVolume.MILLE_CUBIC_FEET,
     },
     SensorDeviceClass.HUMIDITY: {PERCENTAGE},
     SensorDeviceClass.ILLUMINANCE: {LIGHT_LUX},
@@ -654,6 +655,7 @@ DEVICE_CLASS_UNITS: dict[SensorDeviceClass, set[type[StrEnum] | str | None]] = {
         UnitOfVolume.CUBIC_METERS,
         UnitOfVolume.GALLONS,
         UnitOfVolume.LITERS,
+        UnitOfVolume.MILLE_CUBIC_FEET,
     },
     SensorDeviceClass.WEIGHT: set(UnitOfMass),
     SensorDeviceClass.WIND_DIRECTION: {DEGREE},
diff --git a/homeassistant/const.py b/homeassistant/const.py
index 3bd7cc51c7c..d61945e2ef8 100644
--- a/homeassistant/const.py
+++ b/homeassistant/const.py
@@ -766,6 +766,7 @@ class UnitOfVolume(StrEnum):
 
     CUBIC_FEET = "ft³"
     CENTUM_CUBIC_FEET = "CCF"
+    MILLE_CUBIC_FEET = "MCF"
     CUBIC_METERS = "m³"
     LITERS = "L"
     MILLILITERS = "mL"
diff --git a/homeassistant/util/unit_conversion.py b/homeassistant/util/unit_conversion.py
index 918b45ff3c9..1bd40a12d3d 100644
--- a/homeassistant/util/unit_conversion.py
+++ b/homeassistant/util/unit_conversion.py
@@ -752,6 +752,7 @@ class VolumeConverter(BaseUnitConverter):
         UnitOfVolume.CUBIC_METERS: 1,
         UnitOfVolume.CUBIC_FEET: 1 / _CUBIC_FOOT_TO_CUBIC_METER,
         UnitOfVolume.CENTUM_CUBIC_FEET: 1 / (100 * _CUBIC_FOOT_TO_CUBIC_METER),
+        UnitOfVolume.MILLE_CUBIC_FEET: 1 / (1000 * _CUBIC_FOOT_TO_CUBIC_METER),
     }
     VALID_UNITS = {
         UnitOfVolume.LITERS,
@@ -761,6 +762,7 @@ class VolumeConverter(BaseUnitConverter):
         UnitOfVolume.CUBIC_METERS,
         UnitOfVolume.CUBIC_FEET,
         UnitOfVolume.CENTUM_CUBIC_FEET,
+        UnitOfVolume.MILLE_CUBIC_FEET,
     }
 
 
diff --git a/homeassistant/util/unit_system.py b/homeassistant/util/unit_system.py
index 31f74377a16..934cd6d4b69 100644
--- a/homeassistant/util/unit_system.py
+++ b/homeassistant/util/unit_system.py
@@ -281,6 +281,7 @@ METRIC_SYSTEM = UnitSystem(
         # Convert non-metric volumes of gas meters
         ("gas", UnitOfVolume.CENTUM_CUBIC_FEET): UnitOfVolume.CUBIC_METERS,
         ("gas", UnitOfVolume.CUBIC_FEET): UnitOfVolume.CUBIC_METERS,
+        ("gas", UnitOfVolume.MILLE_CUBIC_FEET): UnitOfVolume.CUBIC_METERS,
         # Convert non-metric precipitation
         ("precipitation", UnitOfLength.INCHES): UnitOfLength.MILLIMETERS,
         # Convert non-metric precipitation intensity
@@ -312,10 +313,12 @@ METRIC_SYSTEM = UnitSystem(
         ("volume", UnitOfVolume.CUBIC_FEET): UnitOfVolume.CUBIC_METERS,
         ("volume", UnitOfVolume.FLUID_OUNCES): UnitOfVolume.MILLILITERS,
         ("volume", UnitOfVolume.GALLONS): UnitOfVolume.LITERS,
+        ("volume", UnitOfVolume.MILLE_CUBIC_FEET): UnitOfVolume.CUBIC_METERS,
         # Convert non-metric volumes of water meters
         ("water", UnitOfVolume.CENTUM_CUBIC_FEET): UnitOfVolume.CUBIC_METERS,
         ("water", UnitOfVolume.CUBIC_FEET): UnitOfVolume.CUBIC_METERS,
         ("water", UnitOfVolume.GALLONS): UnitOfVolume.LITERS,
+        ("water", UnitOfVolume.MILLE_CUBIC_FEET): UnitOfVolume.CUBIC_METERS,
         # Convert wind speeds except knots to km/h
         **{
             ("wind_speed", unit): UnitOfSpeed.KILOMETERS_PER_HOUR
diff --git a/tests/components/energy/test_validate.py b/tests/components/energy/test_validate.py
index 9e7a2151b04..9addf6c1001 100644
--- a/tests/components/energy/test_validate.py
+++ b/tests/components/energy/test_validate.py
@@ -850,7 +850,7 @@ async def test_validation_gas(
                     "affected_entities": {("sensor.gas_consumption_1", "beers")},
                     "translation_placeholders": {
                         "energy_units": ENERGY_UNITS_STRING,
-                        "gas_units": "CCF, ft³, m³, L",
+                        "gas_units": "CCF, ft³, m³, L, MCF",
                     },
                 },
                 {
@@ -879,7 +879,7 @@ async def test_validation_gas(
                     "affected_entities": {("sensor.gas_price_2", "EUR/invalid")},
                     "translation_placeholders": {
                         "price_units": (
-                            f"{ENERGY_PRICE_UNITS_STRING}, EUR/CCF, EUR/ft³, EUR/m³, EUR/L"
+                            f"{ENERGY_PRICE_UNITS_STRING}, EUR/CCF, EUR/ft³, EUR/m³, EUR/L, EUR/MCF"
                         )
                     },
                 },
@@ -1060,7 +1060,9 @@ async def test_validation_water(
                 {
                     "type": "entity_unexpected_unit_water",
                     "affected_entities": {("sensor.water_consumption_1", "beers")},
-                    "translation_placeholders": {"water_units": "CCF, ft³, m³, gal, L"},
+                    "translation_placeholders": {
+                        "water_units": "CCF, ft³, m³, gal, L, MCF"
+                    },
                 },
                 {
                     "type": "recorder_untracked",
@@ -1087,7 +1089,7 @@ async def test_validation_water(
                     "type": "entity_unexpected_unit_water_price",
                     "affected_entities": {("sensor.water_price_2", "EUR/invalid")},
                     "translation_placeholders": {
-                        "price_units": "EUR/CCF, EUR/ft³, EUR/m³, EUR/gal, EUR/L"
+                        "price_units": "EUR/CCF, EUR/ft³, EUR/m³, EUR/gal, EUR/L, EUR/MCF"
                     },
                 },
             ],
diff --git a/tests/components/kitchen_sink/snapshots/test_init.ambr b/tests/components/kitchen_sink/snapshots/test_init.ambr
index fe22f19fb7a..c7161a3d284 100644
--- a/tests/components/kitchen_sink/snapshots/test_init.ambr
+++ b/tests/components/kitchen_sink/snapshots/test_init.ambr
@@ -7,7 +7,7 @@
           'metadata_unit': 'm³',
           'state_unit': 'W',
           'statistic_id': 'sensor.statistics_issues_issue_1',
-          'supported_unit': 'CCF, L, fl. oz., ft³, gal, mL, m³',
+          'supported_unit': 'CCF, L, MCF, fl. oz., ft³, gal, mL, m³',
         }),
         'type': 'units_changed',
       }),
@@ -35,7 +35,7 @@
           'metadata_unit': 'm³',
           'state_unit': 'W',
           'statistic_id': 'sensor.statistics_issues_issue_3',
-          'supported_unit': 'CCF, L, fl. oz., ft³, gal, mL, m³',
+          'supported_unit': 'CCF, L, MCF, fl. oz., ft³, gal, mL, m³',
         }),
         'type': 'units_changed',
       }),
diff --git a/tests/components/sensor/test_recorder.py b/tests/components/sensor/test_recorder.py
index 8b6d55cb9a9..09f2480891e 100644
--- a/tests/components/sensor/test_recorder.py
+++ b/tests/components/sensor/test_recorder.py
@@ -5824,7 +5824,7 @@ async def test_validate_statistics_unit_change_equivalent_units(
 @pytest.mark.parametrize(
     ("attributes", "unit1", "unit2", "supported_unit"),
     [
-        (NONE_SENSOR_ATTRIBUTES, "m³", "m3", "CCF, L, fl. oz., ft³, gal, mL, m³"),
+        (NONE_SENSOR_ATTRIBUTES, "m³", "m3", "CCF, L, MCF, fl. oz., ft³, gal, mL, m³"),
         (NONE_SENSOR_ATTRIBUTES, "\u03bcV", "\u00b5V", "MV, V, kV, mV, \u03bcV"),
         (NONE_SENSOR_ATTRIBUTES, "\u03bcS/cm", "\u00b5S/cm", "S/cm, mS/cm, \u03bcS/cm"),
         (
diff --git a/tests/util/test_unit_conversion.py b/tests/util/test_unit_conversion.py
index 476cb667d90..3fe0078aabf 100644
--- a/tests/util/test_unit_conversion.py
+++ b/tests/util/test_unit_conversion.py
@@ -879,6 +879,11 @@ _CONVERTED_VALUE: dict[
         (5, UnitOfVolume.CENTUM_CUBIC_FEET, 478753.24, UnitOfVolume.FLUID_OUNCES),
         (5, UnitOfVolume.CENTUM_CUBIC_FEET, 3740.26, UnitOfVolume.GALLONS),
         (5, UnitOfVolume.CENTUM_CUBIC_FEET, 14158.42, UnitOfVolume.LITERS),
+        (5, UnitOfVolume.MILLE_CUBIC_FEET, 5000, UnitOfVolume.CUBIC_FEET),
+        (5, UnitOfVolume.MILLE_CUBIC_FEET, 141.5842, UnitOfVolume.CUBIC_METERS),
+        (5, UnitOfVolume.MILLE_CUBIC_FEET, 4787532.4, UnitOfVolume.FLUID_OUNCES),
+        (5, UnitOfVolume.MILLE_CUBIC_FEET, 37402.6, UnitOfVolume.GALLONS),
+        (5, UnitOfVolume.MILLE_CUBIC_FEET, 141584.2, UnitOfVolume.LITERS),
     ],
     VolumeFlowRateConverter: [
         (
diff --git a/tests/util/test_unit_system.py b/tests/util/test_unit_system.py
index 87a9729700e..e8da55358a3 100644
--- a/tests/util/test_unit_system.py
+++ b/tests/util/test_unit_system.py
@@ -433,6 +433,11 @@ def test_get_unit_system_invalid(key: str) -> None:
             UnitOfVolume.CENTUM_CUBIC_FEET,
             UnitOfVolume.CUBIC_METERS,
         ),
+        (
+            SensorDeviceClass.GAS,
+            UnitOfVolume.MILLE_CUBIC_FEET,
+            UnitOfVolume.CUBIC_METERS,
+        ),
         (SensorDeviceClass.GAS, UnitOfVolume.CUBIC_FEET, UnitOfVolume.CUBIC_METERS),
         (SensorDeviceClass.GAS, UnitOfVolume.LITERS, None),
         (SensorDeviceClass.GAS, UnitOfVolume.CUBIC_METERS, None),
@@ -510,6 +515,11 @@ def test_get_unit_system_invalid(key: str) -> None:
             UnitOfVolume.CENTUM_CUBIC_FEET,
             UnitOfVolume.CUBIC_METERS,
         ),
+        (
+            SensorDeviceClass.VOLUME,
+            UnitOfVolume.MILLE_CUBIC_FEET,
+            UnitOfVolume.CUBIC_METERS,
+        ),
         (SensorDeviceClass.VOLUME, UnitOfVolume.CUBIC_FEET, UnitOfVolume.CUBIC_METERS),
         (SensorDeviceClass.VOLUME, UnitOfVolume.FLUID_OUNCES, UnitOfVolume.MILLILITERS),
         (SensorDeviceClass.VOLUME, UnitOfVolume.GALLONS, UnitOfVolume.LITERS),
@@ -523,6 +533,11 @@ def test_get_unit_system_invalid(key: str) -> None:
             UnitOfVolume.CENTUM_CUBIC_FEET,
             UnitOfVolume.CUBIC_METERS,
         ),
+        (
+            SensorDeviceClass.WATER,
+            UnitOfVolume.MILLE_CUBIC_FEET,
+            UnitOfVolume.CUBIC_METERS,
+        ),
         (SensorDeviceClass.WATER, UnitOfVolume.CUBIC_FEET, UnitOfVolume.CUBIC_METERS),
         (SensorDeviceClass.WATER, UnitOfVolume.GALLONS, UnitOfVolume.LITERS),
         (SensorDeviceClass.WATER, UnitOfVolume.CUBIC_METERS, None),
@@ -690,6 +705,7 @@ def test_metric_converted_units(device_class: SensorDeviceClass) -> None:
         (SensorDeviceClass.DISTANCE, "very_long", None),
         # Test gas meter conversion
         (SensorDeviceClass.GAS, UnitOfVolume.CENTUM_CUBIC_FEET, None),
+        (SensorDeviceClass.GAS, UnitOfVolume.MILLE_CUBIC_FEET, None),
         (SensorDeviceClass.GAS, UnitOfVolume.CUBIC_METERS, UnitOfVolume.CUBIC_FEET),
         (SensorDeviceClass.GAS, UnitOfVolume.LITERS, UnitOfVolume.CUBIC_FEET),
         (SensorDeviceClass.GAS, UnitOfVolume.CUBIC_FEET, None),
@@ -770,6 +786,7 @@ def test_metric_converted_units(device_class: SensorDeviceClass) -> None:
         (SensorDeviceClass.VOLUME, UnitOfVolume.LITERS, UnitOfVolume.GALLONS),
         (SensorDeviceClass.VOLUME, UnitOfVolume.MILLILITERS, UnitOfVolume.FLUID_OUNCES),
         (SensorDeviceClass.VOLUME, UnitOfVolume.CENTUM_CUBIC_FEET, None),
+        (SensorDeviceClass.VOLUME, UnitOfVolume.MILLE_CUBIC_FEET, None),
         (SensorDeviceClass.VOLUME, UnitOfVolume.CUBIC_FEET, None),
         (SensorDeviceClass.VOLUME, UnitOfVolume.FLUID_OUNCES, None),
         (SensorDeviceClass.VOLUME, UnitOfVolume.GALLONS, None),
@@ -778,6 +795,7 @@ def test_metric_converted_units(device_class: SensorDeviceClass) -> None:
         (SensorDeviceClass.WATER, UnitOfVolume.CUBIC_METERS, UnitOfVolume.CUBIC_FEET),
         (SensorDeviceClass.WATER, UnitOfVolume.LITERS, UnitOfVolume.GALLONS),
         (SensorDeviceClass.WATER, UnitOfVolume.CENTUM_CUBIC_FEET, None),
+        (SensorDeviceClass.WATER, UnitOfVolume.MILLE_CUBIC_FEET, None),
         (SensorDeviceClass.WATER, UnitOfVolume.CUBIC_FEET, None),
         (SensorDeviceClass.WATER, UnitOfVolume.GALLONS, None),
         (SensorDeviceClass.WATER, "very_much", None),
@@ -828,7 +846,11 @@ UNCONVERTED_UNITS_US_SYSTEM = {
         UnitOfLength.MILES,
         UnitOfLength.YARDS,
     ),
-    SensorDeviceClass.GAS: (UnitOfVolume.CENTUM_CUBIC_FEET, UnitOfVolume.CUBIC_FEET),
+    SensorDeviceClass.GAS: (
+        UnitOfVolume.CENTUM_CUBIC_FEET,
+        UnitOfVolume.MILLE_CUBIC_FEET,
+        UnitOfVolume.CUBIC_FEET,
+    ),
     SensorDeviceClass.PRECIPITATION: (UnitOfLength.INCHES,),
     SensorDeviceClass.PRECIPITATION_INTENSITY: (
         UnitOfVolumetricFlux.INCHES_PER_DAY,
@@ -846,12 +868,14 @@ UNCONVERTED_UNITS_US_SYSTEM = {
     ),
     SensorDeviceClass.VOLUME: (
         UnitOfVolume.CENTUM_CUBIC_FEET,
+        UnitOfVolume.MILLE_CUBIC_FEET,
         UnitOfVolume.CUBIC_FEET,
         UnitOfVolume.FLUID_OUNCES,
         UnitOfVolume.GALLONS,
     ),
     SensorDeviceClass.WATER: (
         UnitOfVolume.CENTUM_CUBIC_FEET,
+        UnitOfVolume.MILLE_CUBIC_FEET,
         UnitOfVolume.CUBIC_FEET,
         UnitOfVolume.GALLONS,
     ),