diff --git a/modules/swagger-codegen/src/main/resources/csharp/apiInvoker.mustache b/modules/swagger-codegen/src/main/resources/csharp/apiInvoker.mustache
index f7c76ee2c56..8b58f23e429 100644
--- a/modules/swagger-codegen/src/main/resources/csharp/apiInvoker.mustache
+++ b/modules/swagger-codegen/src/main/resources/csharp/apiInvoker.mustache
@@ -120,7 +120,8 @@
           try
           {
               var webResponse = (HttpWebResponse)client.GetResponse();
-              if (webResponse.StatusCode != HttpStatusCode.OK)
+              int statusCode = (int)webResponse.StatusCode;
+              if (statusCode / 100 != 2) // non-success status
               {
                   webResponse.Close();
                   throw new ApiException((int)webResponse.StatusCode, webResponse.StatusDescription);
diff --git a/samples/client/petstore/csharp/src/main/csharp/io/swagger/client/ApiInvoker.cs b/samples/client/petstore/csharp/src/main/csharp/io/swagger/client/ApiInvoker.cs
index 736b51b81f9..12cc374bf8d 100644
--- a/samples/client/petstore/csharp/src/main/csharp/io/swagger/client/ApiInvoker.cs
+++ b/samples/client/petstore/csharp/src/main/csharp/io/swagger/client/ApiInvoker.cs
@@ -120,7 +120,8 @@ private object invokeAPIInternal(string host, string path, string method, bool b
           try
           {
               var webResponse = (HttpWebResponse)client.GetResponse();
-              if (webResponse.StatusCode != HttpStatusCode.OK)
+              int statusCode = (int)webResponse.StatusCode;
+              if (statusCode / 100 != 2) // non-success status
               {
                   webResponse.Close();
                   throw new ApiException((int)webResponse.StatusCode, webResponse.StatusDescription);