diff --git a/homeassistant/components/derivative/config_flow.py b/homeassistant/components/derivative/config_flow.py
index 726d7616aff..92fff3730a9 100644
--- a/homeassistant/components/derivative/config_flow.py
+++ b/homeassistant/components/derivative/config_flow.py
@@ -24,7 +24,6 @@ from .const import (
 )
 
 UNIT_PREFIXES = [
-    selector.SelectOptionDict(value="none", label="none"),
     selector.SelectOptionDict(value="n", label="n (nano)"),
     selector.SelectOptionDict(value="µ", label="µ (micro)"),
     selector.SelectOptionDict(value="m", label="m (milli)"),
@@ -52,7 +51,7 @@ OPTIONS_SCHEMA = vol.Schema(
             ),
         ),
         vol.Required(CONF_TIME_WINDOW): selector.DurationSelector(),
-        vol.Required(CONF_UNIT_PREFIX, default="none"): selector.SelectSelector(
+        vol.Optional(CONF_UNIT_PREFIX): selector.SelectSelector(
             selector.SelectSelectorConfig(options=UNIT_PREFIXES),
         ),
         vol.Required(CONF_UNIT_TIME, default=UnitOfTime.HOURS): selector.SelectSelector(
diff --git a/homeassistant/components/derivative/sensor.py b/homeassistant/components/derivative/sensor.py
index ba77d2a3d4b..a9c15dfe25e 100644
--- a/homeassistant/components/derivative/sensor.py
+++ b/homeassistant/components/derivative/sensor.py
@@ -116,10 +116,6 @@ async def async_setup_entry(
     else:
         device_info = None
 
-    unit_prefix = config_entry.options[CONF_UNIT_PREFIX]
-    if unit_prefix == "none":
-        unit_prefix = None
-
     derivative_sensor = DerivativeSensor(
         name=config_entry.title,
         round_digits=int(config_entry.options[CONF_ROUND_DIGITS]),
@@ -127,7 +123,7 @@ async def async_setup_entry(
         time_window=cv.time_period_dict(config_entry.options[CONF_TIME_WINDOW]),
         unique_id=config_entry.entry_id,
         unit_of_measurement=None,
-        unit_prefix=unit_prefix,
+        unit_prefix=config_entry.options.get(CONF_UNIT_PREFIX),
         unit_time=config_entry.options[CONF_UNIT_TIME],
         device_info=device_info,
     )
diff --git a/tests/components/derivative/test_config_flow.py b/tests/components/derivative/test_config_flow.py
index 5be99026c77..bc440723df2 100644
--- a/tests/components/derivative/test_config_flow.py
+++ b/tests/components/derivative/test_config_flow.py
@@ -33,7 +33,6 @@ async def test_config_flow(hass: HomeAssistant, platform) -> None:
                 "round": 1,
                 "source": input_sensor_entity_id,
                 "time_window": {"seconds": 0},
-                "unit_prefix": "none",
                 "unit_time": "min",
             },
         )
@@ -47,7 +46,6 @@ async def test_config_flow(hass: HomeAssistant, platform) -> None:
         "round": 1.0,
         "source": "sensor.input",
         "time_window": {"seconds": 0.0},
-        "unit_prefix": "none",
         "unit_time": "min",
     }
     assert len(mock_setup_entry.mock_calls) == 1
@@ -59,7 +57,6 @@ async def test_config_flow(hass: HomeAssistant, platform) -> None:
         "round": 1.0,
         "source": "sensor.input",
         "time_window": {"seconds": 0.0},
-        "unit_prefix": "none",
         "unit_time": "min",
     }
     assert config_entry.title == "My derivative"
@@ -111,7 +108,6 @@ async def test_options(hass: HomeAssistant, platform) -> None:
         user_input={
             "round": 2.0,
             "time_window": {"seconds": 10.0},
-            "unit_prefix": "none",
             "unit_time": "h",
         },
     )
@@ -121,7 +117,6 @@ async def test_options(hass: HomeAssistant, platform) -> None:
         "round": 2.0,
         "source": "sensor.input",
         "time_window": {"seconds": 10.0},
-        "unit_prefix": "none",
         "unit_time": "h",
     }
     assert config_entry.data == {}
@@ -130,7 +125,6 @@ async def test_options(hass: HomeAssistant, platform) -> None:
         "round": 2.0,
         "source": "sensor.input",
         "time_window": {"seconds": 10.0},
-        "unit_prefix": "none",
         "unit_time": "h",
     }
     assert config_entry.title == "My derivative"