diff --git a/src/Kiota.Builder/Writers/TypeScript/CodeConstantWriter.cs b/src/Kiota.Builder/Writers/TypeScript/CodeConstantWriter.cs
index 86be33978e..5b6d9acad2 100644
--- a/src/Kiota.Builder/Writers/TypeScript/CodeConstantWriter.cs
+++ b/src/Kiota.Builder/Writers/TypeScript/CodeConstantWriter.cs
@@ -80,6 +80,10 @@ private static void WriteNavigationMetadataEntry(CodeNamespace parentNamespace,
         if (pathParameters is { Length: > 0 })
             writer.WriteLine($"pathParametersMappings: [{string.Join(", ", pathParameters)}],");
     }
+    private static string GetErrorMappingKey(string original) =>
+    original.Equals("4XX", StringComparison.OrdinalIgnoreCase) || original.Equals("5XX", StringComparison.OrdinalIgnoreCase) ?
+        $"_{original.ToUpperInvariant()}" : // to avoid emitting strings that can't be minified
+        original.ToUpperInvariant();
 
     private void WriteRequestsMetadataConstant(CodeConstant codeElement, LanguageWriter writer)
     {
@@ -105,9 +109,9 @@ private void WriteRequestsMetadataConstant(CodeConstant codeElement, LanguageWri
                 writer.StartBlock("errorMappings: {");
                 foreach (var errorMapping in executorMethod.ErrorMappings)
                 {
-                    writer.WriteLine($"\"{errorMapping.Key.ToUpperInvariant()}\": {GetFactoryMethodName(errorMapping.Value, codeElement, writer)},");
+                    writer.WriteLine($"{GetErrorMappingKey(errorMapping.Key)}: {GetFactoryMethodName(errorMapping.Value, codeElement, writer)} as ParsableFactory<Parsable>,");
                 }
-                writer.CloseBlock("} as Record<string, ParsableFactory<Parsable>>,");
+                writer.CloseBlock("},");
             }
             writer.WriteLine($"adapterMethodName: \"{GetSendRequestMethodName(isVoid, isStream, executorMethod.ReturnType.IsCollection, returnTypeWithoutCollectionSymbol)}\",");
             if (!isVoid)
diff --git a/tests/Kiota.Builder.Tests/Writers/TypeScript/CodeConstantWriterTests.cs b/tests/Kiota.Builder.Tests/Writers/TypeScript/CodeConstantWriterTests.cs
index d8be90451b..918f4ca128 100644
--- a/tests/Kiota.Builder.Tests/Writers/TypeScript/CodeConstantWriterTests.cs
+++ b/tests/Kiota.Builder.Tests/Writers/TypeScript/CodeConstantWriterTests.cs
@@ -322,10 +322,9 @@ public void WritesRequestExecutorBody()
         writer.Write(constant);
         var result = tw.ToString();
         Assert.Contains("errorMappings: {", result);
-        Assert.Contains("4XX\": createError4XXFromDiscriminatorValue", result);
-        Assert.Contains("5XX\": createError5XXFromDiscriminatorValue", result);
-        Assert.Contains("403\": createError403FromDiscriminatorValue", result);
-        Assert.Contains(" as Record<string, ParsableFactory<Parsable>>", result);
+        Assert.Contains("_4XX: createError4XXFromDiscriminatorValue as ParsableFactory<Parsable>", result);
+        Assert.Contains("_5XX: createError5XXFromDiscriminatorValue as ParsableFactory<Parsable>", result);
+        Assert.Contains("403: createError403FromDiscriminatorValue as ParsableFactory<Parsable>", result);
     }
     [Fact]
     public void WritesIndexer()