diff --git a/CRM/Event/BAO/Event.php b/CRM/Event/BAO/Event.php
index e77244bef1f0..df8ece444cc8 100644
--- a/CRM/Event/BAO/Event.php
+++ b/CRM/Event/BAO/Event.php
@@ -1054,7 +1054,7 @@ public static function usesPriceSet($id) {
    * @return array|null
    * @throws \CiviCRM_API3_Exception
    */
-  public static function sendMail($contactID, &$values, $participantId, $isTest = FALSE, $returnMessageText = FALSE) {
+  public static function sendMail($contactID, $values, $participantId, $isTest = FALSE, $returnMessageText = FALSE) {
 
     $template = CRM_Core_Smarty::singleton();
     $gIds = [
diff --git a/CRM/Event/Form/Registration/Confirm.php b/CRM/Event/Form/Registration/Confirm.php
index db2829ef08e5..b5d6739186d7 100644
--- a/CRM/Event/Form/Registration/Confirm.php
+++ b/CRM/Event/Form/Registration/Confirm.php
@@ -928,7 +928,6 @@ public function postProcess() {
 
         //send mail to primary as well as additional participants.
         $this->assign('contactID', $contactId);
-        $this->assign('participantID', $participantID);
         CRM_Event_BAO_Event::sendMail($contactId, $this->_values, $participantID, $isTest);
       }
     }
diff --git a/tests/phpunit/CRM/Event/Form/Registration/ConfirmTest.php b/tests/phpunit/CRM/Event/Form/Registration/ConfirmTest.php
index 782874b2bf0b..683ed6035c36 100644
--- a/tests/phpunit/CRM/Event/Form/Registration/ConfirmTest.php
+++ b/tests/phpunit/CRM/Event/Form/Registration/ConfirmTest.php
@@ -22,6 +22,7 @@ public function setUp() {
    */
   public function testSubmit() {
     $event = $this->eventCreate();
+    $mut = new CiviMailUtils($this, TRUE);
     CRM_Event_Form_Registration_Confirm::testSubmit([
       'id' => $event['id'],
       'contributeMode' => 'direct',
@@ -77,7 +78,15 @@ public function testSubmit() {
         ],
       ],
     ]);
-    $this->callAPISuccessGetSingle('Participant', []);
+    $participant = $this->callAPISuccessGetSingle('Participant', []);
+    $mut->checkMailLog([
+      'Dear Logged In,  Thank you for your participation.  This letter is a confirmation that your registration has been received and your status has been updated to Registered.',
+    ]);
+    $mut->stop();
+    $mut->clearMessages();
+    $tplVars = CRM_Core_Smarty::singleton()->get_template_vars();
+    $this->assertEquals($participant['id'], $tplVars['participantID']);
+
   }
 
   /**
diff --git a/tests/phpunit/CiviTest/CiviUnitTestCase.php b/tests/phpunit/CiviTest/CiviUnitTestCase.php
index 957a716325a7..1343cffa1b42 100644
--- a/tests/phpunit/CiviTest/CiviUnitTestCase.php
+++ b/tests/phpunit/CiviTest/CiviUnitTestCase.php
@@ -1015,6 +1015,7 @@ public function eventCreate($params = array()) {
       'is_monetary' => 0,
       'is_active' => 1,
       'is_show_location' => 0,
+      'is_email_confirm' => 1,
     ), $params);
 
     return $this->callAPISuccess('Event', 'create', $params);
diff --git a/tests/phpunit/api/v3/PaymentTest.php b/tests/phpunit/api/v3/PaymentTest.php
index 6395c462a984..8f0bf927e0f1 100644
--- a/tests/phpunit/api/v3/PaymentTest.php
+++ b/tests/phpunit/api/v3/PaymentTest.php
@@ -167,7 +167,7 @@ public function testPaymentEmailReceiptFullyPaid() {
     $payment = $this->callAPISuccess('payment', 'create', $params);
 
     $this->callAPISuccess('Payment', 'sendconfirmation', ['id' => $payment['id']]);
-    $mut->assertSubjects(['Payment Receipt - Annual CiviCRM meet']);
+    $mut->assertSubjects(['Payment Receipt - Annual CiviCRM meet', 'Registration Confirmation - Annual CiviCRM meet']);
     $mut->checkMailLog([
       'Dear Anthony,',
       'A payment has been received.',