diff --git a/src/services/stringCompletions.ts b/src/services/stringCompletions.ts
index f363ff2fe14..cc0b94507d8 100644
--- a/src/services/stringCompletions.ts
+++ b/src/services/stringCompletions.ts
@@ -223,7 +223,9 @@ namespace ts.Completions.StringCompletions {
     function stringLiteralCompletionsFromProperties(type: Type | undefined): StringLiteralCompletionsFromProperties | undefined {
         return type && {
             kind: StringLiteralCompletionKind.Properties,
-            symbols: type.getApparentProperties().filter(prop => !isPrivateIdentifierPropertyDeclaration(prop.valueDeclaration)),
+            symbols: type.getApparentProperties().filter(prop =>
+                !isPrivateIdentifierPropertyDeclaration(
+                    isTransientSymbol(prop) && prop.syntheticOrigin ? prop.syntheticOrigin.valueDeclaration : prop.valueDeclaration)),
             hasIndexSignature: hasIndexSignature(type)
         };
     }
diff --git a/tests/cases/fourslash/completionForStringLiteral_mappedTypeMembers.ts b/tests/cases/fourslash/completionForStringLiteral_mappedTypeMembers.ts
new file mode 100644
index 00000000000..0822cf9eafa
--- /dev/null
+++ b/tests/cases/fourslash/completionForStringLiteral_mappedTypeMembers.ts
@@ -0,0 +1,18 @@
+/// <reference path='fourslash.ts'/>
+
+////type Foo = {
+////   a: string;
+////   b: string;
+////};
+////
+////type A = Readonly<Foo>;
+////type B = A["[|/**/|]"]
+
+const replacementSpan = test.ranges()[0];
+verify.completions({
+    marker: "",
+    exact: [
+        { name: "a", replacementSpan },
+        { name: "b", replacementSpan }
+    ]
+});