diff --git a/Perspex.Controls/TopLevel.cs b/Perspex.Controls/TopLevel.cs
index 52dde51d96..04cfecdf2c 100644
--- a/Perspex.Controls/TopLevel.cs
+++ b/Perspex.Controls/TopLevel.cs
@@ -299,7 +299,7 @@ namespace Perspex.Controls
                 this.PlatformImpl.ClientSize = finalSize;
             }
 
-            return base.ArrangeOverride(finalSize);
+            return base.ArrangeOverride(this.PlatformImpl.ClientSize);
         }
 
         /// <summary>
diff --git a/Tests/Perspex.Controls.UnitTests/TopLevelTests.cs b/Tests/Perspex.Controls.UnitTests/TopLevelTests.cs
index 7a82ffecf9..0f59636292 100644
--- a/Tests/Perspex.Controls.UnitTests/TopLevelTests.cs
+++ b/Tests/Perspex.Controls.UnitTests/TopLevelTests.cs
@@ -97,6 +97,8 @@ namespace Perspex.Controls.UnitTests
                 Locator.CurrentMutable.RegisterConstant(new LayoutManager(), typeof(ILayoutManager));
 
                 var impl = new Mock<ITopLevelImpl>();
+                impl.SetupProperty(x => x.ClientSize);
+                impl.SetupProperty(x => x.Resized);
 
                 var target = new TestTopLevel(impl.Object)
                 {