diff --git a/src/Mailgun/Api/Suppression/Complaint.php b/src/Mailgun/Api/Suppression/Complaint.php
index ec5575a..cd7a3d9 100644
--- a/src/Mailgun/Api/Suppression/Complaint.php
+++ b/src/Mailgun/Api/Suppression/Complaint.php
@@ -72,10 +72,10 @@ class Complaint extends HttpApi
     {
         Assert::stringNotEmpty($domain);
         Assert::stringNotEmpty($address);
-        Assert::stringNotEmpty($createdAt);
 
         $params['address'] = $address;
         if (null !== $createdAt) {
+            Assert::stringNotEmpty($createdAt);
             $params['created_at'] = $createdAt;
         }
 
diff --git a/tests/Api/Suppression/BounceTest.php b/tests/Api/Suppression/BounceTest.php
index 07b7e05..ef31dbe 100644
--- a/tests/Api/Suppression/BounceTest.php
+++ b/tests/Api/Suppression/BounceTest.php
@@ -67,7 +67,7 @@ class BounceTest extends TestCase
         $this->setHydrateClass(DeleteResponse::class);
 
         $api = $this->getApiInstance();
-        $api->show('example.com', 'foo@bar.com');
+        $api->delete('example.com', 'foo@bar.com');
     }
 
     public function testDeleteAll()
@@ -77,7 +77,7 @@ class BounceTest extends TestCase
         $this->setHydrateClass(DeleteResponse::class);
 
         $api = $this->getApiInstance();
-        $api->show('example.com');
+        $api->deleteAll('example.com');
     }
 
     /**
diff --git a/tests/Api/Suppression/ComplaintTest.php b/tests/Api/Suppression/ComplaintTest.php
new file mode 100644
index 0000000..7eaf62d
--- /dev/null
+++ b/tests/Api/Suppression/ComplaintTest.php
@@ -0,0 +1,89 @@
+<?php
+
+/*
+ * Copyright (C) 2013 Mailgun
+ *
+ * This software may be modified and distributed under the terms
+ * of the MIT license. See the LICENSE file for details.
+ */
+
+namespace Mailgun\Tests\Api;
+
+
+
+use Mailgun\Api\Suppression\Complaint;
+use Mailgun\Model\Suppression\Complaint\CreateResponse;
+use Mailgun\Model\Suppression\Complaint\DeleteResponse;
+use Mailgun\Model\Suppression\Complaint\IndexResponse;
+use Mailgun\Model\Suppression\Complaint\ShowResponse;
+
+
+/**
+ *
+ *
+ * @author Tobias Nyholm <tobias.nyholm@gmail.com>
+ */
+class ComplaintTest extends TestCase
+{
+    public function testIndex()
+    {
+        $this->setRequestMethod('GET');
+        $this->setRequestUri('/v3/example.com/complaints?limit=100');
+        $this->setHydrateClass(IndexResponse::class);
+
+        $api = $this->getApiInstance();
+        $api->index('example.com');
+    }
+
+    public function testShow()
+    {
+        $this->setRequestMethod('GET');
+        $this->setRequestUri('/v3/example.com/complaints/foo@bar.com');
+        $this->setHydrateClass(ShowResponse::class);
+
+        $api = $this->getApiInstance();
+        $api->show('example.com', 'foo@bar.com');
+    }
+
+    public function testCreate()
+    {
+        $this->setRequestMethod('POST');
+        $this->setRequestUri('/v3/example.com/complaints');
+        $this->setHydrateClass(CreateResponse::class);
+        $this->setRequestBody([
+            'address' => 'foo@bar.com',
+        ]);
+
+        $api = $this->getApiInstance();
+        $api->create('example.com', 'foo@bar.com');
+    }
+
+
+    public function testDelete()
+    {
+        $this->setRequestMethod('DELETE');
+        $this->setRequestUri('/v3/example.com/complaints/foo@bar.com');
+        $this->setHydrateClass(DeleteResponse::class);
+
+        $api = $this->getApiInstance();
+        $api->delete('example.com', 'foo@bar.com');
+    }
+
+    public function testDeleteAll()
+    {
+        $this->setRequestMethod('DELETE');
+        $this->setRequestUri('/v3/example.com/complaints');
+        $this->setHydrateClass(DeleteResponse::class);
+
+        $api = $this->getApiInstance();
+        $api->deleteAll('example.com');
+    }
+
+    /**
+     * {@inheritdoc}
+     */
+    protected function getApiClass()
+    {
+        return Complaint::class;
+    }
+}