diff --git a/homeassistant/components/wallbox/__init__.py b/homeassistant/components/wallbox/__init__.py
index e5c8b7719a3a5ef0e48e5db9c902708741d0e5be..410a3115f9fe9fb3208ebdfcd6fae0a21f8f85e5 100644
--- a/homeassistant/components/wallbox/__init__.py
+++ b/homeassistant/components/wallbox/__init__.py
@@ -75,7 +75,7 @@ class WallboxCoordinator(DataUpdateCoordinator):
             filtered_data = {k: data[k] for k in CONF_SENSOR_TYPES if k in data}
 
             for key, value in filtered_data.items():
-                if sensor_round := CONF_SENSOR_TYPES[key][CONF_ROUND]:
+                if (sensor_round := CONF_SENSOR_TYPES[key][CONF_ROUND]) is not None:
                     try:
                         filtered_data[key] = round(value, sensor_round)
                     except TypeError:
diff --git a/tests/components/wallbox/__init__.py b/tests/components/wallbox/__init__.py
index 4a403d0afc8390650f4802052cfbed1924854229..f8031bd86a4991648d6fc672acf5e5ac1a08a7ca 100644
--- a/tests/components/wallbox/__init__.py
+++ b/tests/components/wallbox/__init__.py
@@ -31,7 +31,7 @@ test_response = json.loads(
     json.dumps(
         {
             CONF_CHARGING_POWER_KEY: 0,
-            CONF_MAX_AVAILABLE_POWER_KEY: 25,
+            CONF_MAX_AVAILABLE_POWER_KEY: 25.2,
             CONF_CHARGING_SPEED_KEY: 0,
             CONF_ADDED_RANGE_KEY: "xx",
             CONF_ADDED_ENERGY_KEY: "44.697",
diff --git a/tests/components/wallbox/const.py b/tests/components/wallbox/const.py
index 3aa2dde38f022c89fee89389741a1519848e11fa..9777602f6c9083245986307947e84b752cabb4b7 100644
--- a/tests/components/wallbox/const.py
+++ b/tests/components/wallbox/const.py
@@ -8,3 +8,4 @@ CONF_STATUS = "status"
 CONF_MOCK_NUMBER_ENTITY_ID = "number.mock_title_max_charging_current"
 CONF_MOCK_SENSOR_CHARGING_SPEED_ID = "sensor.mock_title_charging_speed"
 CONF_MOCK_SENSOR_CHARGING_POWER_ID = "sensor.mock_title_charging_power"
+CONF_MOCK_SENSOR_MAX_AVAILABLE_POWER = "sensor.mock_title_max_available_power"
diff --git a/tests/components/wallbox/test_sensor.py b/tests/components/wallbox/test_sensor.py
index 41dcd0e6ee00894f156407627b8fe1ec23e2b15b..2551eed6a2efe4a7ee2b259c9343345dcc220f80 100644
--- a/tests/components/wallbox/test_sensor.py
+++ b/tests/components/wallbox/test_sensor.py
@@ -5,6 +5,7 @@ from tests.components.wallbox import entry, setup_integration
 from tests.components.wallbox.const import (
     CONF_MOCK_SENSOR_CHARGING_POWER_ID,
     CONF_MOCK_SENSOR_CHARGING_SPEED_ID,
+    CONF_MOCK_SENSOR_MAX_AVAILABLE_POWER,
 )
 
 
@@ -21,4 +22,8 @@ async def test_wallbox_sensor_class(hass):
     assert state.attributes[CONF_ICON] == "mdi:speedometer"
     assert state.name == "Mock Title Charging Speed"
 
+    # Test round with precision '0' works
+    state = hass.states.get(CONF_MOCK_SENSOR_MAX_AVAILABLE_POWER)
+    assert state.state == "25.0"
+
     await hass.config_entries.async_unload(entry.entry_id)