diff --git a/lib/emailable/client.rb b/lib/emailable/client.rb
index a61369f..e738740 100644
--- a/lib/emailable/client.rb
+++ b/lib/emailable/client.rb
@@ -22,7 +22,7 @@ def request(method, endpoint, params = {})
 
       uri = URI("#{@base_url}/#{endpoint}")
       headers = {
-        'Authorization': "Bearer #{Emailable.api_key || api_key || access_token}",
+        'Authorization': "Bearer #{api_key || access_token || Emailable.api_key}",
         'Content-Type': 'application/json'
       }
 
diff --git a/test/authentication_test.rb b/test/authentication_test.rb
index 7ec2f82..1692754 100644
--- a/test/authentication_test.rb
+++ b/test/authentication_test.rb
@@ -24,4 +24,10 @@ def test_request_time_api_key_authentication
     refute_nil Emailable::Batch.new(bid).status(api_key: @api_key).id
   end
 
+  def test_request_time_authentication_takes_priority_over_global
+    Emailable.api_key = 'invalid_api_key'
+
+    refute_nil Emailable.verify(@email, api_key: @api_key).domain
+  end
+
 end