diff --git a/src/compiler/checker.ts b/src/compiler/checker.ts
index 7101d0b3d61d7..719ba724f4237 100644
--- a/src/compiler/checker.ts
+++ b/src/compiler/checker.ts
@@ -13850,7 +13850,7 @@ namespace ts {
             if (!switchTypes.length) {
                 return false;
             }
-            return eachTypeContainedIn(type, switchTypes);
+            return eachTypeContainedIn(mapType(type, getRegularTypeOfLiteralType), switchTypes);
         }
 
         function functionHasImplicitReturn(func: FunctionLikeDeclaration) {