diff --git a/homeassistant/components/uptimerobot/sensor.py b/homeassistant/components/uptimerobot/sensor.py
index 7a241d6999be..60866154ac0e 100644
--- a/homeassistant/components/uptimerobot/sensor.py
+++ b/homeassistant/components/uptimerobot/sensor.py
@@ -37,11 +37,12 @@ async def async_setup_entry(
     known_devices: set[int] = set()
 
     def _check_device() -> None:
-        current_devices = {monitor.id for monitor in coordinator.data}
-        new_devices = current_devices - known_devices
-        if new_devices:
-            known_devices.update(new_devices)
-            async_add_entities(
+        entities: list[UptimeRobotSensor] = []
+        for monitor in coordinator.data:
+            if monitor.id in known_devices:
+                continue
+            known_devices.add(monitor.id)
+            entities.append(
                 UptimeRobotSensor(
                     coordinator,
                     SensorEntityDescription(
@@ -59,9 +60,9 @@ async def async_setup_entry(
                     ),
                     monitor=monitor,
                 )
-                for monitor in coordinator.data
-                if monitor.id in new_devices
             )
+        if entities:
+            async_add_entities(entities)
 
     _check_device()
     entry.async_on_unload(coordinator.async_add_listener(_check_device))
diff --git a/homeassistant/components/uptimerobot/switch.py b/homeassistant/components/uptimerobot/switch.py
index 531131034ce0..41a46e9ff5cf 100644
--- a/homeassistant/components/uptimerobot/switch.py
+++ b/homeassistant/components/uptimerobot/switch.py
@@ -34,11 +34,12 @@ async def async_setup_entry(
     known_devices: set[int] = set()
 
     def _check_device() -> None:
-        current_devices = {monitor.id for monitor in coordinator.data}
-        new_devices = current_devices - known_devices
-        if new_devices:
-            known_devices.update(new_devices)
-            async_add_entities(
+        entities: list[UptimeRobotSwitch] = []
+        for monitor in coordinator.data:
+            if monitor.id in known_devices:
+                continue
+            known_devices.add(monitor.id)
+            entities.append(
                 UptimeRobotSwitch(
                     coordinator,
                     SwitchEntityDescription(
@@ -47,9 +48,9 @@ async def async_setup_entry(
                     ),
                     monitor=monitor,
                 )
-                for monitor in coordinator.data
-                if monitor.id in new_devices
             )
+        if entities:
+            async_add_entities(entities)
 
     _check_device()
     entry.async_on_unload(coordinator.async_add_listener(_check_device))