diff --git a/lib/netsuite/actions/async_upsert_list.rb b/lib/netsuite/actions/async_upsert_list.rb
new file mode 100644
index 000000000..bdf436841
--- /dev/null
+++ b/lib/netsuite/actions/async_upsert_list.rb
@@ -0,0 +1,118 @@
+# https://system.netsuite.com/help/helpcenter/en_US/Output/Help/SuiteCloudCustomizationScriptingWebServices/SuiteTalkWebServices/upsertList.html
+module NetSuite
+  module Actions
+    class AsyncUpsertList < AbstractAction
+      include Support::Requests
+
+      def initialize(*objects)
+        @objects = objects
+      end
+
+      private
+
+      # <soap:Body>
+      #   <asyncUpsertList>
+      #     <record xsi:type="listRel:Customer" externalId="ext1">
+      #       <listRel:entityId>Shutter Fly</listRel:entityId>
+      #       <listRel:companyName>Shutter Fly, Inc</listRel:companyName>
+      #     </record>
+      #     <record xsi:type="listRel:Customer" externalId="ext2">
+      #       <listRel:entityId>Target</listRel:entityId>
+      #       <listRel:companyName>Target</listRel:companyName>
+      #     </record>
+      #   </asyncUpsertList>
+      # </soap:Body>
+      def request_body
+        attrs = @objects.map do |o|
+          hash = o.to_record.merge({
+            '@xsi:type' => o.record_type
+          })
+
+          if o.respond_to?(:external_id) && o.external_id
+            hash['@externalId'] = o.external_id
+          end
+
+          hash
+        end
+
+        { 'record' => attrs }
+      end
+
+      def response_hash
+        @response_hash ||= Array[@response.body[:upsert_list_response][:write_response_list][:write_response]].flatten
+      end
+
+      def response_body
+        @response_body ||= response_hash.map { |h| h[:base_ref] }
+      end
+
+      def response_errors
+        if response_hash.any? { |h| h[:status] && h[:status][:status_detail] }
+          @response_errors ||= errors
+        end
+      end
+
+      def errors
+        errors = response_hash.select { |h| h[:status] && h[:status][:status_detail] }.map do |obj|
+          error_obj = obj[:status][:status_detail]
+          error_obj = [error_obj] if error_obj.class == Hash
+          errors = error_obj.map do |error|
+            NetSuite::Error.new(error)
+          end
+
+          [obj[:base_ref][:@external_id], errors]
+        end
+        Hash[errors]
+      end
+
+      def success?
+        @success ||= response_hash.all? { |h| h[:status][:@is_success] == 'true' }
+      end
+
+      def request_options
+        {
+          element_form_default: :unqualified
+        }
+      end
+
+      def action_name
+        :async_upsert_list
+      end
+
+      module Support
+
+        def self.included(base)
+          base.extend(ClassMethods)
+        end
+
+        module ClassMethods
+          def async_upsert_list(records, credentials = {})
+            netsuite_records = records.map do |r|
+              if r.kind_of?(self)
+                r
+              else
+                self.new(r)
+              end
+            end
+
+            response = NetSuite::Actions::AsyncUpsertList.call(netsuite_records, credentials)
+
+            if response.success?
+              response.body.map do |attr|
+                record = netsuite_records.find do |r|
+                  r.external_id == attr[:@external_id]
+                end
+
+                record.instance_variable_set('@internal_id', attr[:@internal_id])
+              end
+
+              netsuite_records
+            else
+              false
+            end
+          end
+        end
+      end
+    end
+  end
+end