diff --git a/src/libraries/System.Private.CoreLib/src/System/Globalization/TextInfo.cs b/src/libraries/System.Private.CoreLib/src/System/Globalization/TextInfo.cs
index 06d9ac7e041882..109ebde2c24dd4 100644
--- a/src/libraries/System.Private.CoreLib/src/System/Globalization/TextInfo.cs
+++ b/src/libraries/System.Private.CoreLib/src/System/Globalization/TextInfo.cs
@@ -37,7 +37,7 @@ private enum Tristate : byte
         private Tristate _isAsciiCasingSameAsInvariant = Tristate.NotInitialized;
 
         // Invariant text info
-        internal static readonly TextInfo Invariant = new TextInfo(CultureData.Invariant, readOnly: true);
+        internal static readonly TextInfo Invariant = new TextInfo(CultureData.Invariant, readOnly: true) { _isAsciiCasingSameAsInvariant = Tristate.True };
 
         internal TextInfo(CultureData cultureData)
         {