diff --git a/src/Compilers/CSharp/Test/Semantic/Semantics/InterpolationTests.cs b/src/Compilers/CSharp/Test/Semantic/Semantics/InterpolationTests.cs
index 6d829cd9dcdf2..6b2079bf5f1a6 100644
--- a/src/Compilers/CSharp/Test/Semantic/Semantics/InterpolationTests.cs
+++ b/src/Compilers/CSharp/Test/Semantic/Semantics/InterpolationTests.cs
@@ -4873,6 +4873,7 @@ public void HandlerConversionPreferredOverStringForNonConstant(string expression
             var code = @"
 CultureInfoNormalizer.Normalize();
 C.M(" + expression + @");
+CultureInfoNormalizer.Reset();
 class C
 {
     public static void M(CustomHandler b)
@@ -4896,7 +4897,7 @@ public static void M(string s)
 
             verifier.VerifyIL(@"<top-level-statements-entry-point>", @"
 {
-  // Code size       55 (0x37)
+  // Code size       60 (0x3c)
   .maxstack  4
   .locals init (CustomHandler V_0)
   IL_0000:  call       ""void CultureInfoNormalizer.Normalize()""
@@ -4919,7 +4920,8 @@ .locals init (CustomHandler V_0)
   IL_002f:  pop
   IL_0030:  ldloc.0
   IL_0031:  call       ""void C.M(CustomHandler)""
-  IL_0036:  ret
+  IL_0036:  call       ""void CultureInfoNormalizer.Reset()""
+  IL_003b:  ret
 }
 ");
 
@@ -4928,7 +4930,7 @@ .locals init (CustomHandler V_0)
 
             verifier.VerifyIL(@"<top-level-statements-entry-point>", expression.Contains('+') ? @"
 {
-  // Code size       37 (0x25)
+  // Code size       42 (0x2a)
   .maxstack  2
   IL_0000:  call       ""void CultureInfoNormalizer.Normalize()""
   IL_0005:  ldstr      ""{0,2:f}""
@@ -4938,12 +4940,13 @@ .maxstack  2
   IL_0015:  ldstr      ""Literal""
   IL_001a:  call       ""string string.Concat(string, string)""
   IL_001f:  call       ""void C.M(string)""
-  IL_0024:  ret
+  IL_0024:  call       ""void CultureInfoNormalizer.Reset()""
+  IL_0029:  ret
 }
 "
 : @"
 {
-  // Code size       27 (0x1b)
+  // Code size       32 (0x20)
   .maxstack  2
   IL_0000:  call       ""void CultureInfoNormalizer.Normalize()""
   IL_0005:  ldstr      ""{0,2:f}Literal""
@@ -4951,7 +4954,8 @@ .maxstack  2
   IL_000b:  box        ""int""
   IL_0010:  call       ""string string.Format(string, object)""
   IL_0015:  call       ""void C.M(string)""
-  IL_001a:  ret
+  IL_001a:  call       ""void CultureInfoNormalizer.Reset()""
+  IL_001f:  ret
 }
 ");
         }
@@ -5422,6 +5426,7 @@ public void LambdaReturnInference_02(string expression)
 using System;
 CultureInfoNormalizer.Normalize();
 C.M(() => " + expression + @");
+CultureInfoNormalizer.Reset();
 
 class C
 {
@@ -5669,6 +5674,7 @@ public void LambdaReturnInference_06(string expression)
         if (b) return default(CustomHandler);
         else return " + expression + @";
     });
+CultureInfoNormalizer.Reset();
 
 static class C
 {
@@ -5922,6 +5928,7 @@ public void TernaryTypes_02(string expression)
 CultureInfoNormalizer.Normalize();
 var x = (bool)(object)false ? default(CustomHandler) : " + expression + @";
 Console.WriteLine(x);
+CultureInfoNormalizer.Reset();
 
 public partial struct CustomHandler
 {
@@ -5934,7 +5941,7 @@ public partial struct CustomHandler
 
             verifier.VerifyIL("<top-level-statements-entry-point>", !expression.Contains('+') ? @"
 {
-  // Code size       56 (0x38)
+  // Code size       61 (0x3d)
   .maxstack  2
   .locals init (CustomHandler V_0)
   IL_0000:  call       ""void CultureInfoNormalizer.Normalize()""
@@ -5952,12 +5959,13 @@ .locals init (CustomHandler V_0)
   IL_002c:  ldloc.0
   IL_002d:  call       ""string CustomHandler.op_Implicit(CustomHandler)""
   IL_0032:  call       ""void System.Console.WriteLine(string)""
-  IL_0037:  ret
+  IL_0037:  call       ""void CultureInfoNormalizer.Reset()""
+  IL_003c:  ret
 }
 "
 : @"
 {
-  // Code size       66 (0x42)
+  // Code size       71 (0x47)
   .maxstack  2
   .locals init (CustomHandler V_0)
   IL_0000:  call       ""void CultureInfoNormalizer.Normalize()""
@@ -5977,7 +5985,8 @@ .locals init (CustomHandler V_0)
   IL_0036:  ldloc.0
   IL_0037:  call       ""string CustomHandler.op_Implicit(CustomHandler)""
   IL_003c:  call       ""void System.Console.WriteLine(string)""
-  IL_0041:  ret
+  IL_0041:  call       ""void CultureInfoNormalizer.Reset()""
+  IL_0046:  ret
 }
 ");
         }
@@ -6190,6 +6199,7 @@ public void SwitchTypes_02(string expression)
 CultureInfoNormalizer.Normalize();
 var x = (bool)(object)false switch { true => default(CustomHandler), false => " + expression + @" };
 Console.WriteLine(x);
+CultureInfoNormalizer.Reset();
 
 public partial struct CustomHandler
 {
@@ -6202,7 +6212,7 @@ public partial struct CustomHandler
 
             verifier.VerifyIL("<top-level-statements-entry-point>", !expression.Contains('+') ? @"
 {
-  // Code size       59 (0x3b)
+  // Code size       64 (0x40)
   .maxstack  2
   .locals init (string V_0,
                 CustomHandler V_1)
@@ -6224,12 +6234,13 @@ .locals init (string V_0,
   IL_0033:  stloc.0
   IL_0034:  ldloc.0
   IL_0035:  call       ""void System.Console.WriteLine(string)""
-  IL_003a:  ret
+  IL_003a:  call       ""void CultureInfoNormalizer.Reset()""
+  IL_003f:  ret
 }
 "
 : @"
 {
-  // Code size       69 (0x45)
+  // Code size       74 (0x4a)
   .maxstack  2
   .locals init (string V_0,
                 CustomHandler V_1)
@@ -6253,7 +6264,8 @@ .locals init (string V_0,
   IL_003d:  stloc.0
   IL_003e:  ldloc.0
   IL_003f:  call       ""void System.Console.WriteLine(string)""
-  IL_0044:  ret
+  IL_0044:  call       ""void CultureInfoNormalizer.Reset()""
+  IL_0049:  ret
 }
 ");
         }
diff --git a/src/Compilers/CSharp/Test/Semantic/Semantics/RawInterpolationTests_Handler.cs b/src/Compilers/CSharp/Test/Semantic/Semantics/RawInterpolationTests_Handler.cs
index bde5a43a8840b..ee7f1463e8e58 100644
--- a/src/Compilers/CSharp/Test/Semantic/Semantics/RawInterpolationTests_Handler.cs
+++ b/src/Compilers/CSharp/Test/Semantic/Semantics/RawInterpolationTests_Handler.cs
@@ -3633,6 +3633,7 @@ public void LambdaReturnInference_02(string expression)
 using System;
 CultureInfoNormalizer.Normalize();
 C.M(() => " + expression + @");
+CultureInfoNormalizer.Reset();
 
 class C
 {
@@ -3902,6 +3903,7 @@ public void LambdaReturnInference_06(string expression)
         if (b) return default(CustomHandler);
         else return " + expression + @";
     });
+CultureInfoNormalizer.Reset();
 
 static class C
 {
@@ -4178,6 +4180,7 @@ public void TernaryTypes_02(string expression)
 CultureInfoNormalizer.Normalize();
 var x = (bool)(object)false ? default(CustomHandler) : " + expression + @";
 Console.WriteLine(x);
+CultureInfoNormalizer.Reset();
 
 public partial struct CustomHandler
 {
@@ -4190,7 +4193,7 @@ public partial struct CustomHandler
 
         verifier.VerifyIL("<top-level-statements-entry-point>", !expression.Contains('+') ? @"
 {
-  // Code size       56 (0x38)
+  // Code size       61 (0x3d)
   .maxstack  2
   .locals init (CustomHandler V_0)
   IL_0000:  call       ""void CultureInfoNormalizer.Normalize()""
@@ -4208,12 +4211,13 @@ .locals init (CustomHandler V_0)
   IL_002c:  ldloc.0
   IL_002d:  call       ""string CustomHandler.op_Implicit(CustomHandler)""
   IL_0032:  call       ""void System.Console.WriteLine(string)""
-  IL_0037:  ret
+  IL_0037:  call       ""void CultureInfoNormalizer.Reset()""
+  IL_003c:  ret
 }
 "
 : @"
 {
-  // Code size       66 (0x42)
+  // Code size       71 (0x47)
   .maxstack  2
   .locals init (CustomHandler V_0)
   IL_0000:  call       ""void CultureInfoNormalizer.Normalize()""
@@ -4233,7 +4237,8 @@ .locals init (CustomHandler V_0)
   IL_0036:  ldloc.0
   IL_0037:  call       ""string CustomHandler.op_Implicit(CustomHandler)""
   IL_003c:  call       ""void System.Console.WriteLine(string)""
-  IL_0041:  ret
+  IL_0041:  call       ""void CultureInfoNormalizer.Reset()""
+  IL_0046:  ret
 }
 ");
     }
@@ -4443,6 +4448,7 @@ public void SwitchTypes_02(string expression)
 CultureInfoNormalizer.Normalize();
 var x = (bool)(object)false switch { true => default(CustomHandler), false => " + expression + @" };
 Console.WriteLine(x);
+CultureInfoNormalizer.Reset();
 
 public partial struct CustomHandler
 {
@@ -4455,7 +4461,7 @@ public partial struct CustomHandler
 
         verifier.VerifyIL("<top-level-statements-entry-point>", !expression.Contains('+') ? @"
 {
-  // Code size       59 (0x3b)
+  // Code size       64 (0x40)
   .maxstack  2
   .locals init (string V_0,
                 CustomHandler V_1)
@@ -4477,12 +4483,13 @@ .locals init (string V_0,
   IL_0033:  stloc.0
   IL_0034:  ldloc.0
   IL_0035:  call       ""void System.Console.WriteLine(string)""
-  IL_003a:  ret
+  IL_003a:  call       ""void CultureInfoNormalizer.Reset()""
+  IL_003f:  ret
 }
 "
 : @"
 {
-  // Code size       69 (0x45)
+  // Code size       74 (0x4a)
   .maxstack  2
   .locals init (string V_0,
                 CustomHandler V_1)
@@ -4506,7 +4513,8 @@ .locals init (string V_0,
   IL_003d:  stloc.0
   IL_003e:  ldloc.0
   IL_003f:  call       ""void System.Console.WriteLine(string)""
-  IL_0044:  ret
+  IL_0044:  call       ""void CultureInfoNormalizer.Reset()""
+  IL_0049:  ret
 }
 ");
     }
diff --git a/src/Compilers/Test/Utilities/CSharp/CSharpTestBase.cs b/src/Compilers/Test/Utilities/CSharp/CSharpTestBase.cs
index 166457fffd27e..32197356378ef 100644
--- a/src/Compilers/Test/Utilities/CSharp/CSharpTestBase.cs
+++ b/src/Compilers/Test/Utilities/CSharp/CSharpTestBase.cs
@@ -2544,10 +2544,18 @@ internal static string GetInterpolatedStringCustomHandlerType(string name, strin
             var cultureInfoHandler = @"
 public class CultureInfoNormalizer
 {
+    private static CultureInfo originalCulture;
+
     public static void Normalize()
     {
+        originalCulture = CultureInfo.CurrentCulture;
         CultureInfo.CurrentCulture = CultureInfo.InvariantCulture;
     }
+
+    public static void Reset()
+    {
+        CultureInfo.CurrentCulture = originalCulture;
+    }
 }
 ";