diff --git a/src/Configuration.php b/src/Configuration.php
index <HASH>..<HASH> 100644
--- a/src/Configuration.php
+++ b/src/Configuration.php
@@ -91,6 +91,10 @@ final class Configuration
      */
     public function setRecipientOverride($recipientOverride)
     {
+        if (!$recipientOverride) {
+            return $this;
+        }
+
         if (!filter_var($recipientOverride, FILTER_VALIDATE_EMAIL)) {
             throw new Exception('Recipient override must be a valid email address');
         }
diff --git a/tests/ConfigurationTest.php b/tests/ConfigurationTest.php
index <HASH>..<HASH> 100644
--- a/tests/ConfigurationTest.php
+++ b/tests/ConfigurationTest.php
@@ -78,6 +78,17 @@ final class ConfigurationTest extends PHPUnit_Framework_TestCase
     /**
      * @test
      */
+    public function it_ignores_an_empty_recipient_override()
+    {
+        $config = Configuration::newInstance()
+            ->setRecipientOverride(null);
+
+        $this->assertSame('', $config->getRecipientOverride());
+    }
+
+    /**
+     * @test
+     */
     public function it_states_that_Gmail_style_overriding_should_be_done_when_configured_so()
     {
         $config = Configuration::newInstance()
Ignore empty recipient override