diff --git a/app/Jobs/Mail/NinjaMailer.php b/app/Jobs/Mail/NinjaMailer.php
index 8deffe484352..726327dba855 100644
--- a/app/Jobs/Mail/NinjaMailer.php
+++ b/app/Jobs/Mail/NinjaMailer.php
@@ -43,7 +43,7 @@ class NinjaMailer extends Mailable
         $ninja_mailable = $this->from(config('mail.from.address'), $from_name)
                     ->subject($this->mail_obj->subject)
                     ->view($this->mail_obj->markdown, $this->mail_obj->data)
-                    ->withSwiftMessage(function ($message) {
+                    ->withSymfonyMessage(function ($message) {
                         $message->getHeaders()->addTextHeader('Tag', $this->mail_obj->tag);
                     });
 
diff --git a/app/Jobs/Mail/NinjaMailerJob.php b/app/Jobs/Mail/NinjaMailerJob.php
index c63e87f93491..680b493caa15 100644
--- a/app/Jobs/Mail/NinjaMailerJob.php
+++ b/app/Jobs/Mail/NinjaMailerJob.php
@@ -212,7 +212,7 @@ class NinjaMailerJob implements ShouldQueue
         $this->nmo
              ->mailable
              ->from($user->email, $user->name())
-             ->withSwiftMessage(function ($message) use ($token) {
+             ->withSymfonyMessage(function ($message) use ($token) {
                  $message->getHeaders()->addTextHeader('GmailToken', $token);
              });
 
@@ -277,7 +277,7 @@ class NinjaMailerJob implements ShouldQueue
         $this->nmo
              ->mailable
              ->from($user->email, $user->name())
-             ->withSwiftMessage(function ($message) use ($token) {
+             ->withSymfonyMessage(function ($message) use ($token) {
                  $message->getHeaders()->addTextHeader('GmailToken', $token);
              });
     }
diff --git a/app/Mail/Admin/EntityNotificationMailer.php b/app/Mail/Admin/EntityNotificationMailer.php
index cd9afda9a6b4..8f2718de6eb9 100644
--- a/app/Mail/Admin/EntityNotificationMailer.php
+++ b/app/Mail/Admin/EntityNotificationMailer.php
@@ -37,7 +37,7 @@ class EntityNotificationMailer extends Mailable
         return $this->from(config('mail.from.address'), config('mail.from.name'))
                     ->subject($this->mail_obj->subject)
                     ->markdown($this->mail_obj->markdown, $this->mail_obj->data)
-                    ->withSwiftMessage(function ($message) {
+                    ->withSymfonyMessage(function ($message) {
                         $message->getHeaders()->addTextHeader('Tag', $this->mail_obj->tag);
                     });
     }
diff --git a/app/Mail/TemplateEmail.php b/app/Mail/TemplateEmail.php
index 819f06e1aac5..63727a173721 100644
--- a/app/Mail/TemplateEmail.php
+++ b/app/Mail/TemplateEmail.php
@@ -114,7 +114,7 @@ class TemplateEmail extends Mailable
                 'whitelabel' => $this->client->user->account->isPaid() ? true : false,
                 'logo' => $this->company->present()->logo($settings),
             ])
-            ->withSwiftMessage(function ($message) use ($company) {
+            ->withSymfonyMessage(function ($message) use ($company) {
                 $message->getHeaders()->addTextHeader('Tag', $company->company_key);
                 $message->invitation = $this->invitation;
             });
diff --git a/app/Mail/User/UserNotificationMailer.php b/app/Mail/User/UserNotificationMailer.php
index 123602a738af..6d04e0bf01b9 100644
--- a/app/Mail/User/UserNotificationMailer.php
+++ b/app/Mail/User/UserNotificationMailer.php
@@ -42,7 +42,7 @@ class UserNotificationMailer extends Mailable
                 'body' => $this->mail_obj->data['message'],
             ])
             ->view($this->mail_obj->markdown, $this->mail_obj->data)
-            ->withSwiftMessage(function ($message) {
+            ->withSymfonyMessage(function ($message) {
                 $message->getHeaders()->addTextHeader('Tag', $this->mail_obj->tag);
             });
     }
diff --git a/app/Mail/VendorTemplateEmail.php b/app/Mail/VendorTemplateEmail.php
index e935fb5e6133..080783dab330 100644
--- a/app/Mail/VendorTemplateEmail.php
+++ b/app/Mail/VendorTemplateEmail.php
@@ -108,7 +108,7 @@ class VendorTemplateEmail extends Mailable
                 'whitelabel' => $this->vendor->user->account->isPaid() ? true : false,
                 'logo' => $this->company->present()->logo($settings),
             ])
-            ->withSwiftMessage(function ($message) {
+            ->withSymfonyMessage(function ($message) {
                 $message->getHeaders()->addTextHeader('Tag', $this->company->company_key);
                 $message->invitation = $this->invitation;
             });
diff --git a/app/Notifications/BaseNotification.php b/app/Notifications/BaseNotification.php
index a9d430def162..ee3ad743f571 100644
--- a/app/Notifications/BaseNotification.php
+++ b/app/Notifications/BaseNotification.php
@@ -98,7 +98,7 @@ class BaseNotification extends Notification
             $mail_message->attachData($ubl_string, $this->entity->getFileName('xml'));
         }
 
-        return $mail_message->withSwiftMessage(function ($message) {
+        return $mail_message->withSymfonyMessage(function ($message) {
             $message->getHeaders()->addTextHeader('Tag', $this->invitation->company->company_key);
         });
     }
diff --git a/app/Providers/MailServiceProvider.php b/app/Providers/MailServiceProvider.php
index 75da4da52653..e5cac4003698 100644
--- a/app/Providers/MailServiceProvider.php
+++ b/app/Providers/MailServiceProvider.php
@@ -28,7 +28,7 @@ class MailServiceProvider extends MailProvider
 
     public function boot()
     {
-        app('mail.manager')->getSwiftMailer()->registerPlugin($this->app->make(CssInlinerPlugin::class));
+        app('mail.manager')->getSymfonyTransport()->registerPlugin($this->app->make(CssInlinerPlugin::class));
     }
 
     protected function registerIlluminateMailer()
diff --git a/composer.json b/composer.json
index 7772221d2d06..64253fffdefd 100644
--- a/composer.json
+++ b/composer.json
@@ -85,13 +85,13 @@
         "socialiteproviders/microsoft": "^4.1",
         "square/square": "13.0.0.20210721",
         "stripe/stripe-php": "^7.50",
-        "symfony/http-client": "^5.2",
+        "symfony/http-client": "^6.0",
         "tijsverkoyen/css-to-inline-styles": "^2.2",
         "turbo124/beacon": "^1.0",
         "turbo124/laravel-gmail": "^5",
         "webpatser/laravel-countries": "dev-master#75992ad",
         "wepay/php-sdk": "^0.3",
-        "wildbit/swiftmailer-postmark": "^3.3"
+        "symfony/postmark-mailer": "^6.0"
     },
     "require-dev": {
         "php": "^7.4|^8.0",