diff --git a/src/Uno.UI.Tests/Windows_UI_XAML_Controls/TextBoxTests/Given_TextBox.cs b/src/Uno.UI.Tests/Windows_UI_XAML_Controls/TextBoxTests/Given_TextBox.cs
index dc7e7f58df50..3a92003d4c1b 100644
--- a/src/Uno.UI.Tests/Windows_UI_XAML_Controls/TextBoxTests/Given_TextBox.cs
+++ b/src/Uno.UI.Tests/Windows_UI_XAML_Controls/TextBoxTests/Given_TextBox.cs
@@ -39,11 +39,19 @@ public void When_Setting_Text_Null()
 			textBox.Text = "Rhubarb";
 			Assert.AreEqual("Rhubarb", textBox.Text);
 			Assert.AreEqual(1, callbackCount);
-			
+
+#if !HAS_UNO_WINUI
+			// Setting TextBox.Text to null throws an exception in UWP but not WinUI.
 			Assert.ThrowsException<ArgumentNullException>(() => textBox.Text = null);
+#endif
 
 			Assert.AreEqual("Rhubarb", textBox.Text);
 			Assert.AreEqual(1, callbackCount);
+
+#if HAS_UNO_WINUI
+			textBox.Text = null;
+			Assert.AreEqual("", textBox.Text);
+#endif
 		}
 
 		[TestMethod]
diff --git a/src/Uno.UI/UI/Xaml/Controls/TextBox/TextBox.cs b/src/Uno.UI/UI/Xaml/Controls/TextBox/TextBox.cs
index a0cbf28a2ee7..d752248fcd8f 100644
--- a/src/Uno.UI/UI/Xaml/Controls/TextBox/TextBox.cs
+++ b/src/Uno.UI/UI/Xaml/Controls/TextBox/TextBox.cs
@@ -193,7 +193,11 @@ public string Text
 			{
 				if (value == null)
 				{
+#if HAS_UNO_WINUI
+					value = string.Empty;
+#else
 					throw new ArgumentNullException();
+#endif
 				}
 
 				this.SetValue(TextProperty, value);