diff --git a/app/Models/InstanceSettings.php b/app/Models/InstanceSettings.php
index 7110b8cff..5b89bb401 100644
--- a/app/Models/InstanceSettings.php
+++ b/app/Models/InstanceSettings.php
@@ -16,7 +16,19 @@ class InstanceSettings extends Model implements SendsEmail
     protected $guarded = [];
 
     protected $casts = [
+        'smtp_enabled' => 'boolean',
+        'smtp_from_address' => 'encrypted',
+        'smtp_from_name' => 'encrypted',
+        'smtp_recipients' => 'encrypted',
+        'smtp_host' => 'encrypted',
+        'smtp_port' => 'integer',
+        'smtp_username' => 'encrypted',
         'smtp_password' => 'encrypted',
+        'smtp_timeout' => 'integer',
+
+        'resend_enabled' => 'boolean',
+        'resend_api_key' => 'encrypted',
+
         'allowed_ip_ranges' => 'array',
         'is_auto_update_enabled' => 'boolean',
         'auto_update_frequency' => 'string',