diff --git a/lib/smartystreets_ruby_sdk/us_street/client.rb b/lib/smartystreets_ruby_sdk/us_street/client.rb
index c8eed99..40e58ed 100644
--- a/lib/smartystreets_ruby_sdk/us_street/client.rb
+++ b/lib/smartystreets_ruby_sdk/us_street/client.rb
@@ -61,7 +61,7 @@ def remap_keys(obj)
           converted_lookup['urbanization'] = lookup.urbanization
           converted_lookup['match'] = lookup.match
           converted_lookup['candidates'] = lookup.candidates
-
+          converted_lookup['format'] = lookup.format
           converted_obj.push(converted_lookup)
         end
         converted_obj
diff --git a/lib/smartystreets_ruby_sdk/us_street/lookup.rb b/lib/smartystreets_ruby_sdk/us_street/lookup.rb
index ba5984d..0b3d48b 100644
--- a/lib/smartystreets_ruby_sdk/us_street/lookup.rb
+++ b/lib/smartystreets_ruby_sdk/us_street/lookup.rb
@@ -9,10 +9,10 @@ module USStreet
     # @match:: Must be set to 'strict', 'range', or 'invalid'. Constants for these are in match_type.rb
     class Lookup < JSONAble
       attr_accessor :input_id, :street, :street2, :secondary, :city, :state, :zipcode, :lastline, :addressee, :urbanization,
-                    :match, :candidates, :result
+                    :match, :candidates, :format, :result
 
       def initialize(street=nil, street2=nil, secondary=nil, city=nil, state=nil, zipcode=nil, lastline=nil,
-                     addressee=nil, urbanization=nil, match=nil, candidates=0, input_id=nil)
+                     addressee=nil, urbanization=nil, match=nil, candidates=0, input_id=nil, format=nil)
         @input_id = input_id
         @street = street
         @street2 = street2
@@ -25,6 +25,7 @@ def initialize(street=nil, street2=nil, secondary=nil, city=nil, state=nil, zipc
         @urbanization = urbanization
         @match = match
         @candidates = candidates
+        @format = format
         @result = []
       end
     end
diff --git a/lib/smartystreets_ruby_sdk/us_street/match_type.rb b/lib/smartystreets_ruby_sdk/us_street/match_type.rb
index 11a9d7f..53782f5 100644
--- a/lib/smartystreets_ruby_sdk/us_street/match_type.rb
+++ b/lib/smartystreets_ruby_sdk/us_street/match_type.rb
@@ -6,5 +6,11 @@ module MatchType
       INVALID = 'invalid'.freeze
       ENHANCED = 'enhanced'.freeze
     end
+
+    module OutputFormat
+      DEFAULT = 'default'.freeze
+      PROJECT_USA = 'project-usa'.freeze
+      CASS = 'cass'.freeze
+    end
   end
 end
diff --git a/test/smartystreets_ruby_sdk/us_street/test_street_client.rb b/test/smartystreets_ruby_sdk/us_street/test_street_client.rb
index eafb47c..f5f719d 100644
--- a/test/smartystreets_ruby_sdk/us_street/test_street_client.rb
+++ b/test/smartystreets_ruby_sdk/us_street/test_street_client.rb
@@ -38,7 +38,8 @@ def test_send_populated_lookup
         'addressee' => '9',
         'urbanization' => '10',
         'match' => SmartyStreets::USStreet::MatchType::ENHANCED,
-        'candidates' => 5
+        'candidates' => 5,
+        'format' => SmartyStreets::USStreet::OutputFormat::PROJECT_USA,
     }
     serializer = FakeSerializer.new(expected_parameters)
     client = Client.new(sender, serializer)
@@ -54,7 +55,7 @@ def test_send_populated_lookup
     lookup.addressee = '9'
     lookup.urbanization = '10'
     lookup.match = SmartyStreets::USStreet::MatchType::ENHANCED
-
+    lookup.format = SmartyStreets::USStreet::OutputFormat::PROJECT_USA
     client.send_lookup(lookup)
 
     assert_equal(expected_parameters, sender.request.parameters)