diff --git a/lib/help_scout.rb b/lib/help_scout.rb
index 872275c..cb9da80 100644
--- a/lib/help_scout.rb
+++ b/lib/help_scout.rb
@@ -115,7 +115,6 @@ def reports_user_ratings(user_id, rating, start_date, end_date, options)
     get("reports/user/ratings", options)
   end
 
-
   # Public: Creates conversation thread
   #
   # conversion_id - conversation id
@@ -138,6 +137,16 @@ def create_thread(conversation_id:, thread:, imported: nil, reload: nil)
     last_response.code == HTTP_CREATED
   end
 
+  # Public: Update Customer
+  #
+  # id - customer id
+  # data - hash with data
+  #
+  # More info: http://developer.helpscout.net/help-desk-api/customers/update/
+  def update_customer(id, data)
+    put("customers/#{id}", { body: data })
+  end
+
   protected
 
   def post(path, options = {})
diff --git a/spec/helpscout_spec.rb b/spec/helpscout_spec.rb
index 84697e3..eb01f5f 100644
--- a/spec/helpscout_spec.rb
+++ b/spec/helpscout_spec.rb
@@ -112,4 +112,18 @@
       expect(req).to have_been_requested
     end
   end
+
+  describe '#update_customer' do
+    let(:data) { { "firstName" => "Bob" } }
+
+    it 'does the correct query' do
+      url = 'https://api.helpscout.net/v1/customers/1337.json'
+      req = stub_request(:put, url).
+        with(body: data.to_json).
+        to_return(status: 201)
+
+      client.update_customer(1337, data)
+      expect(req).to have_been_requested
+    end
+  end
 end