diff --git a/homeassistant/components/hassio/update.py b/homeassistant/components/hassio/update.py
index afe62408ef55..07a4bf42b2ad 100644
--- a/homeassistant/components/hassio/update.py
+++ b/homeassistant/components/hassio/update.py
@@ -257,7 +257,9 @@ class SupervisorOSUpdateEntity(HassioOSEntity, UpdateEntity):
     def installed_version(self) -> str | None:
         """Return the installed version."""
         assert self.coordinator.data.os is not None
-        return self.coordinator.data.os.version
+        return (
+            self.coordinator.data.os.version_pending or self.coordinator.data.os.version
+        )
 
     @property
     @override
diff --git a/tests/components/hassio/test_update.py b/tests/components/hassio/test_update.py
index 6dbd236771e4..de88658557cc 100644
--- a/tests/components/hassio/test_update.py
+++ b/tests/components/hassio/test_update.py
@@ -71,6 +71,7 @@ def mock_all(
         os_info.return_value,
         version="1.0.0dev2221",
         version_latest="1.0.0dev2222",
+        version_pending=None,
         update_available=True,
     )
     supervisor_info.return_value = replace(
@@ -540,10 +541,11 @@ async def test_update_os(
     await hass.async_block_till_done()
 
     async def mock_os_update(*args: Any) -> None:
-        """Simulate Supervisor reporting the new version after the update."""
+        """Simulate Supervisor keeping version stable while pending version updates."""
         os_info.return_value = replace(
             os_info.return_value,
-            version="1.0.0dev2222",
+            version="1.0.0dev2221",
+            version_pending="1.0.0dev2222",
             update_available=False,
         )
 
@@ -560,8 +562,8 @@ async def test_update_os(
     mock_create_backup.assert_not_called()
     supervisor_client.os.update.assert_called_once_with(OSUpdate(version=None))
 
-    # The coordinator is refreshed after install so the new version
-    # shows up immediately
+    # The coordinator refresh reflects the new pending version while
+    # the base version remains unchanged.
     state = hass.states.get("update.home_assistant_operating_system_update")
     assert state is not None
     assert state.state == "off"