diff --git a/Authenticatable.php b/Authenticatable.php
index 46101d2aa..ae55d8fec 100644
--- a/Authenticatable.php
+++ b/Authenticatable.php
@@ -4,6 +4,16 @@
 
 trait Authenticatable
 {
+    /**
+     * Get the name of the unique identifier for the user.
+     *
+     * @return string
+     */
+    public function getAuthIdentifierName()
+    {
+        return $this->getKeyName();
+    }
+
     /**
      * Get the unique identifier for the user.
      *
diff --git a/EloquentUserProvider.php b/EloquentUserProvider.php
index e2b6dc7df..0df8c50c8 100755
--- a/EloquentUserProvider.php
+++ b/EloquentUserProvider.php
@@ -59,7 +59,7 @@ public function retrieveByToken($identifier, $token)
         $model = $this->createModel();
 
         return $model->newQuery()
-            ->where($model->getKeyName(), $identifier)
+            ->where($model->getAuthIdentifierName(), $identifier)
             ->where($model->getRememberTokenName(), $token)
             ->first();
     }
diff --git a/GenericUser.php b/GenericUser.php
index d349d4983..b6880c0ca 100755
--- a/GenericUser.php
+++ b/GenericUser.php
@@ -24,6 +24,16 @@ public function __construct(array $attributes)
         $this->attributes = $attributes;
     }
 
+    /**
+     * Get the name of the unique identifier for the user.
+     *
+     * @return string
+     */
+    public function getAuthIdentifierName()
+    {
+        return 'id';
+    }
+
     /**
      * Get the unique identifier for the user.
      *
@@ -31,7 +41,9 @@ public function __construct(array $attributes)
      */
     public function getAuthIdentifier()
     {
-        return $this->attributes['id'];
+        $name = $this->getAuthIdentifierName();
+
+        return $this->attributes[$name];
     }
 
     /**