diff --git a/src/Symfony/Bridge/Doctrine/Security/User/UserLoaderInterface.php b/src/Symfony/Bridge/Doctrine/Security/User/UserLoaderInterface.php
index b190eb249967a..551017c313315 100644
--- a/src/Symfony/Bridge/Doctrine/Security/User/UserLoaderInterface.php
+++ b/src/Symfony/Bridge/Doctrine/Security/User/UserLoaderInterface.php
@@ -29,4 +29,10 @@
  */
 interface UserLoaderInterface
 {
+    /**
+     * @return UserInterface|null
+     *
+     * @deprecated since Symfony 5.3, use loadUserByIdentifier() instead
+     */
+    public function loadUserByUsername(string $username);
 }
diff --git a/src/Symfony/Component/Security/Core/Authentication/RememberMe/PersistentTokenInterface.php b/src/Symfony/Component/Security/Core/Authentication/RememberMe/PersistentTokenInterface.php
index 85c5bc385e580..18eea22587b98 100644
--- a/src/Symfony/Component/Security/Core/Authentication/RememberMe/PersistentTokenInterface.php
+++ b/src/Symfony/Component/Security/Core/Authentication/RememberMe/PersistentTokenInterface.php
@@ -48,4 +48,11 @@ public function getTokenValue();
      * @return \DateTime
      */
     public function getLastUsed();
+
+    /**
+     * @return string
+     *
+     * @deprecated since Symfony 5.3, use getUserIdentifier() instead
+     */
+    public function getUsername();
 }
diff --git a/src/Symfony/Component/Security/Core/Authentication/Token/TokenInterface.php b/src/Symfony/Component/Security/Core/Authentication/Token/TokenInterface.php
index 047f571ae4a20..82633f92051f3 100644
--- a/src/Symfony/Component/Security/Core/Authentication/Token/TokenInterface.php
+++ b/src/Symfony/Component/Security/Core/Authentication/Token/TokenInterface.php
@@ -130,4 +130,11 @@ public function __serialize(): array;
      * Restores the object state from an array given by __serialize().
      */
     public function __unserialize(array $data): void;
+
+    /**
+     * @return string
+     *
+     * @deprecated since Symfony 5.3, use getUserIdentifier() instead
+     */
+    public function getUsername();
 }
diff --git a/src/Symfony/Component/Security/Core/User/UserInterface.php b/src/Symfony/Component/Security/Core/User/UserInterface.php
index 6448ab519248d..f30d36e17d4d6 100644
--- a/src/Symfony/Component/Security/Core/User/UserInterface.php
+++ b/src/Symfony/Component/Security/Core/User/UserInterface.php
@@ -78,4 +78,11 @@ public function getSalt();
      * the plain-text password is stored on this object.
      */
     public function eraseCredentials();
+
+    /**
+     * @return string
+     *
+     * @deprecated since Symfony 5.3, use getUserIdentifier() instead
+     */
+    public function getUsername();
 }
diff --git a/src/Symfony/Component/Security/Core/User/UserProviderInterface.php b/src/Symfony/Component/Security/Core/User/UserProviderInterface.php
index 5ab67836c730f..2444bdfa242d6 100644
--- a/src/Symfony/Component/Security/Core/User/UserProviderInterface.php
+++ b/src/Symfony/Component/Security/Core/User/UserProviderInterface.php
@@ -57,4 +57,13 @@ public function refreshUser(UserInterface $user);
      * @return bool
      */
     public function supportsClass(string $class);
+
+    /**
+     * @return UserInterface
+     *
+     * @throws UserNotFoundException
+     *
+     * @deprecated since Symfony 5.3, use loadUserByIdentifier() instead
+     */
+    public function loadUserByUsername(string $username);
 }
diff --git a/src/Symfony/Component/Security/Http/Tests/LoginLink/LoginLinkHandlerTest.php b/src/Symfony/Component/Security/Http/Tests/LoginLink/LoginLinkHandlerTest.php
index 02f6f0182f503..877e1b62bdb57 100644
--- a/src/Symfony/Component/Security/Http/Tests/LoginLink/LoginLinkHandlerTest.php
+++ b/src/Symfony/Component/Security/Http/Tests/LoginLink/LoginLinkHandlerTest.php
@@ -211,6 +211,11 @@ public function createUser(TestLoginLinkHandlerUser $user): void
         $this->users[$user->getUserIdentifier()] = $user;
     }
 
+    public function loadUserByUsername($username): TestLoginLinkHandlerUser
+    {
+        return $this->loadUserByIdentifier($username);
+    }
+
     public function loadUserByIdentifier(string $userIdentifier): TestLoginLinkHandlerUser
     {
         if (!isset($this->users[$userIdentifier])) {