diff --git a/homeassistant/components/tplink/light.py b/homeassistant/components/tplink/light.py
index 65967eb6bea..d0c056d7c17 100644
--- a/homeassistant/components/tplink/light.py
+++ b/homeassistant/components/tplink/light.py
@@ -269,7 +269,7 @@ class TPLinkSmartBulb(CoordinatedTPLinkEntity, LightEntity):
     @property
     def brightness(self) -> int | None:
         """Return the brightness of this light between 0..255."""
-        return round((self.device.brightness * 255.0) / 100.0)
+        return round((cast(int, self.device.brightness) * 255.0) / 100.0)
 
     @property
     def hs_color(self) -> tuple[int, int] | None: