diff --git a/gems/aws-sdk-core/lib/aws-sdk-core/plugins/protocols/rpc_v2.rb b/gems/aws-sdk-core/lib/aws-sdk-core/plugins/protocols/rpc_v2.rb
index 34bfcdaa97..ff2a42da94 100644
--- a/gems/aws-sdk-core/lib/aws-sdk-core/plugins/protocols/rpc_v2.rb
+++ b/gems/aws-sdk-core/lib/aws-sdk-core/plugins/protocols/rpc_v2.rb
@@ -7,7 +7,7 @@ class RpcV2 < Seahorse::Client::Plugin
 
         option(:protocol, 'smithy-rpc-v2-cbor')
 
-        option(:one_pass_serde, true, docstring: 'When true, use one pass serde which avoid intermediate hash use')
+        option(:one_pass_serde, false, docstring: 'When true, use one pass serde which avoid intermediate hash use')
 
         handler(Aws::RpcV2::Handler)
         handler(Aws::RpcV2::ContentTypeHandler, priority: 30)