diff --git a/intern/cycles/render/tile.cpp b/intern/cycles/render/tile.cpp
index e59d0c843a3..a493c3fa1cd 100644
--- a/intern/cycles/render/tile.cpp
+++ b/intern/cycles/render/tile.cpp
@@ -157,7 +157,7 @@ void TileManager::set_samples(int num_samples_)
 			divider >>= 1;
 		}
 
-		state.total_pixel_samples = pixel_samples + get_num_effective_samples() * params.width*params.height;
+		state.total_pixel_samples = pixel_samples + (uint64_t)get_num_effective_samples() * params.width*params.height;
 	}
 }