diff --git a/CRM/Utils/Mail/Incoming.php b/CRM/Utils/Mail/Incoming.php
index 23a4e803a2bd..7f27bab67007 100644
--- a/CRM/Utils/Mail/Incoming.php
+++ b/CRM/Utils/Mail/Incoming.php
@@ -367,8 +367,7 @@ private static function parseAddress($address, &$subParam, &$mail, $createContac
 
     $contactID = self::getContactID($subParam['email'],
       $subParam['name'],
-      $createContact,
-      $mail
+      $createContact
     );
     $subParam['id'] = $contactID ?: NULL;
   }
@@ -397,11 +396,12 @@ private static function parseAddresses(&$addresses, $token, &$params, &$mail, $c
    * @param string $email
    * @param string $name
    * @param bool $create
-   * @param string $mail
+   *
+   * @internal core use only (only use outside this class is in core unit tests).
    *
    * @return int|null
    */
-  public static function getContactID($email, $name, $create, &$mail) {
+  public static function getContactID($email, $name, $create) {
     $dao = CRM_Contact_BAO_Contact::matchContactOnEmail($email, 'Individual');
 
     $contactID = NULL;
diff --git a/tests/phpunit/CRM/Utils/Mail/IncomingTest.php b/tests/phpunit/CRM/Utils/Mail/IncomingTest.php
index aebc2fab72e2..14ac2b4cef93 100644
--- a/tests/phpunit/CRM/Utils/Mail/IncomingTest.php
+++ b/tests/phpunit/CRM/Utils/Mail/IncomingTest.php
@@ -46,7 +46,7 @@ public function setUp(): void {
   public function testEmailUseExistentIndividualContact(): void {
     $expectedContactId = $this->individualCreate(['email' => $this->email]);
 
-    $receivedContactId = CRM_Utils_Mail_Incoming::getContactID($this->email, $this->name, TRUE, $mail);
+    $receivedContactId = CRM_Utils_Mail_Incoming::getContactID($this->email, $this->name, TRUE);
 
     $this->assertEquals($expectedContactId, $receivedContactId);
   }
@@ -58,7 +58,7 @@ public function testEmailCreateIndividualContact(): void {
     $contact = CRM_Contact_BAO_Contact::matchContactOnEmail($this->email, 'Individual');
     $this->assertNull($contact);
 
-    CRM_Utils_Mail_Incoming::getContactID($this->email, $this->name, TRUE, $mail);
+    CRM_Utils_Mail_Incoming::getContactID($this->email, $this->name, TRUE);
 
     $contact = CRM_Contact_BAO_Contact::matchContactOnEmail($this->email, 'Individual');
     $this->assertNotNull($contact);
@@ -70,7 +70,7 @@ public function testEmailCreateIndividualContact(): void {
   public function testEmailUseExistentOrganizationContact(): void {
     $expectedContactId = $this->organizationCreate(['email' => $this->email]);
 
-    $receivedContactId = CRM_Utils_Mail_Incoming::getContactID($this->email, $this->name, TRUE, $mail);
+    $receivedContactId = CRM_Utils_Mail_Incoming::getContactID($this->email, $this->name, TRUE);
 
     $this->assertEquals($expectedContactId, $receivedContactId);
   }
@@ -82,7 +82,7 @@ public function testEmailPrefersExistentIndividualContact(): void {
     $individualContactId = $this->individualCreate(['email' => $this->email]);
     $this->organizationCreate(['email' => $this->email]);
 
-    $receivedContactId = CRM_Utils_Mail_Incoming::getContactID($this->email, $this->name, TRUE, $mail);
+    $receivedContactId = CRM_Utils_Mail_Incoming::getContactID($this->email, $this->name, TRUE);
 
     $this->assertEquals($individualContactId, $receivedContactId);
   }