diff --git a/homeassistant/components/whois/sensor.py b/homeassistant/components/whois/sensor.py
index 2cbae147a78..0459651e693 100644
--- a/homeassistant/components/whois/sensor.py
+++ b/homeassistant/components/whois/sensor.py
@@ -80,6 +80,13 @@ def _ensure_timezone(timestamp: datetime | None) -> datetime | None:
     return timestamp
 
 
+def _fetch_attr_if_exists(domain: Domain, attr: str) -> str | None:
+    """Fetch an attribute if it exists and is truthy or return None."""
+    if hasattr(domain, attr) and (value := getattr(domain, attr)):
+        return cast(str, value)
+    return None
+
+
 SENSORS: tuple[WhoisSensorEntityDescription, ...] = (
     WhoisSensorEntityDescription(
         key="admin",
@@ -87,7 +94,7 @@ SENSORS: tuple[WhoisSensorEntityDescription, ...] = (
         icon="mdi:account-star",
         entity_category=EntityCategory.DIAGNOSTIC,
         entity_registry_enabled_default=False,
-        value_fn=lambda domain: domain.admin if domain.admin else None,
+        value_fn=lambda domain: _fetch_attr_if_exists(domain, "admin"),
     ),
     WhoisSensorEntityDescription(
         key="creation_date",
@@ -123,7 +130,7 @@ SENSORS: tuple[WhoisSensorEntityDescription, ...] = (
         icon="mdi:account",
         entity_category=EntityCategory.DIAGNOSTIC,
         entity_registry_enabled_default=False,
-        value_fn=lambda domain: domain.owner if domain.owner else None,
+        value_fn=lambda domain: _fetch_attr_if_exists(domain, "owner"),
     ),
     WhoisSensorEntityDescription(
         key="registrant",
@@ -131,7 +138,7 @@ SENSORS: tuple[WhoisSensorEntityDescription, ...] = (
         icon="mdi:account-edit",
         entity_category=EntityCategory.DIAGNOSTIC,
         entity_registry_enabled_default=False,
-        value_fn=lambda domain: domain.registrant if domain.registrant else None,
+        value_fn=lambda domain: _fetch_attr_if_exists(domain, "registrant"),
     ),
     WhoisSensorEntityDescription(
         key="registrar",
@@ -147,7 +154,7 @@ SENSORS: tuple[WhoisSensorEntityDescription, ...] = (
         icon="mdi:store",
         entity_category=EntityCategory.DIAGNOSTIC,
         entity_registry_enabled_default=False,
-        value_fn=lambda domain: domain.reseller if domain.reseller else None,
+        value_fn=lambda domain: _fetch_attr_if_exists(domain, "reseller"),
     ),
 )
 
@@ -190,7 +197,6 @@ async def async_setup_entry(
             )
             for description in SENSORS
         ],
-        update_before_add=True,
     )
 
 
diff --git a/tests/components/whois/conftest.py b/tests/components/whois/conftest.py
index bbda3b101f5..ef14750356e 100644
--- a/tests/components/whois/conftest.py
+++ b/tests/components/whois/conftest.py
@@ -3,7 +3,7 @@ from __future__ import annotations
 
 from collections.abc import Generator
 from datetime import datetime
-from unittest.mock import AsyncMock, MagicMock, patch
+from unittest.mock import AsyncMock, MagicMock, Mock, patch
 
 import pytest
 
@@ -71,6 +71,33 @@ def mock_whois() -> Generator[MagicMock, None, None]:
         yield whois_mock
 
 
+@pytest.fixture
+def mock_whois_missing_some_attrs() -> Generator[Mock, None, None]:
+    """Return a mocked query that only sets admin."""
+
+    class LimitedWhoisMock:
+        """A limited mock of whois_query."""
+
+        def __init__(self, *args, **kwargs):
+            """Mock only attributes the library always sets being available."""
+            self.creation_date = datetime(2019, 1, 1, 0, 0, 0)
+            self.dnssec = True
+            self.expiration_date = datetime(2023, 1, 1, 0, 0, 0)
+            self.last_updated = datetime(
+                2022, 1, 1, 0, 0, 0, tzinfo=dt_util.get_time_zone("Europe/Amsterdam")
+            )
+            self.name = "home-assistant.io"
+            self.name_servers = ["ns1.example.com", "ns2.example.com"]
+            self.registrar = "My Registrar"
+            self.status = "OK"
+            self.statuses = ["OK"]
+
+    with patch(
+        "homeassistant.components.whois.whois_query", LimitedWhoisMock
+    ) as whois_mock:
+        yield whois_mock
+
+
 @pytest.fixture
 async def init_integration(
     hass: HomeAssistant, mock_config_entry: MockConfigEntry, mock_whois: MagicMock
@@ -84,6 +111,21 @@ async def init_integration(
     return mock_config_entry
 
 
+@pytest.fixture
+async def init_integration_missing_some_attrs(
+    hass: HomeAssistant,
+    mock_config_entry: MockConfigEntry,
+    mock_whois_missing_some_attrs: MagicMock,
+) -> MockConfigEntry:
+    """Set up thewhois integration for testing."""
+    mock_config_entry.add_to_hass(hass)
+
+    await hass.config_entries.async_setup(mock_config_entry.entry_id)
+    await hass.async_block_till_done()
+
+    return mock_config_entry
+
+
 @pytest.fixture
 def enable_all_entities() -> Generator[AsyncMock, None, None]:
     """Test fixture that ensures all entities are enabled in the registry."""
diff --git a/tests/components/whois/test_init.py b/tests/components/whois/test_init.py
index 6701d8ed20c..3cd9efc801d 100644
--- a/tests/components/whois/test_init.py
+++ b/tests/components/whois/test_init.py
@@ -30,7 +30,7 @@ async def test_load_unload_config_entry(
     await hass.async_block_till_done()
 
     assert mock_config_entry.state is ConfigEntryState.LOADED
-    assert len(mock_whois.mock_calls) == 2
+    assert len(mock_whois.mock_calls) == 1
 
     await hass.config_entries.async_unload(mock_config_entry.entry_id)
     await hass.async_block_till_done()
@@ -76,5 +76,5 @@ async def test_import_config(
     await hass.async_block_till_done()
 
     assert len(hass.config_entries.async_entries(DOMAIN)) == 1
-    assert len(mock_whois.mock_calls) == 2
+    assert len(mock_whois.mock_calls) == 1
     assert "the Whois platform in YAML is deprecated" in caplog.text
diff --git a/tests/components/whois/test_sensor.py b/tests/components/whois/test_sensor.py
index b0e9862eb64..e824522ed09 100644
--- a/tests/components/whois/test_sensor.py
+++ b/tests/components/whois/test_sensor.py
@@ -143,6 +143,32 @@ async def test_whois_sensors(
     assert device_entry.sw_version is None
 
 
+@pytest.mark.freeze_time("2022-01-01 12:00:00", tz_offset=0)
+async def test_whois_sensors_missing_some_attrs(
+    hass: HomeAssistant,
+    enable_all_entities: AsyncMock,
+    init_integration_missing_some_attrs: MockConfigEntry,
+) -> None:
+    """Test the Whois sensors with owner and reseller missing."""
+    entity_registry = er.async_get(hass)
+
+    state = hass.states.get("sensor.home_assistant_io_last_updated")
+    entry = entity_registry.async_get("sensor.home_assistant_io_last_updated")
+    assert entry
+    assert state
+    assert entry.unique_id == "home-assistant.io_last_updated"
+    assert entry.entity_category == EntityCategory.DIAGNOSTIC
+    assert state.state == "2021-12-31T23:00:00+00:00"
+    assert state.attributes.get(ATTR_FRIENDLY_NAME) == "home-assistant.io Last Updated"
+    assert state.attributes.get(ATTR_DEVICE_CLASS) == SensorDeviceClass.TIMESTAMP
+    assert ATTR_ICON not in state.attributes
+
+    assert hass.states.get("sensor.home_assistant_io_owner").state == STATE_UNKNOWN
+    assert hass.states.get("sensor.home_assistant_io_reseller").state == STATE_UNKNOWN
+    assert hass.states.get("sensor.home_assistant_io_registrant").state == STATE_UNKNOWN
+    assert hass.states.get("sensor.home_assistant_io_admin").state == STATE_UNKNOWN
+
+
 @pytest.mark.parametrize(
     "entity_id",
     (