diff --git a/mailpoet/lib/Automation/Integrations/MailPoet/MailPoetIntegration.php b/mailpoet/lib/Automation/Integrations/MailPoet/MailPoetIntegration.php
index 60100c9d39..438627738e 100644
--- a/mailpoet/lib/Automation/Integrations/MailPoet/MailPoetIntegration.php
+++ b/mailpoet/lib/Automation/Integrations/MailPoet/MailPoetIntegration.php
@@ -11,6 +11,7 @@ use MailPoet\Automation\Integrations\MailPoet\Subjects\SegmentSubject;
 use MailPoet\Automation\Integrations\MailPoet\Subjects\SubscriberSubject;
 use MailPoet\Automation\Integrations\MailPoet\SubjectTransformers\OrderSubjectToSegmentSubjectTransformer;
 use MailPoet\Automation\Integrations\MailPoet\SubjectTransformers\OrderSubjectToSubscriberSubjectTransformer;
+use MailPoet\Automation\Integrations\MailPoet\SubjectTransformers\SubscriberSubjectToWordPressUserSubjectTransformer;
 use MailPoet\Automation\Integrations\MailPoet\Triggers\SomeoneSubscribesTrigger;
 use MailPoet\Automation\Integrations\MailPoet\Triggers\UserRegistrationTrigger;
 
@@ -45,12 +46,16 @@ class MailPoetIntegration implements Integration {
   /** @var OrderSubjectToSegmentSubjectTransformer */
   private $orderToSegmentTransformer;
 
+  /** @var SubscriberSubjectToWordPressUserSubjectTransformer */
+  private $subscriberToWordPressUserTransformer;
+
   public function __construct(
     ContextFactory $contextFactory,
     SegmentSubject $segmentSubject,
     SubscriberSubject $subscriberSubject,
     OrderSubjectToSubscriberSubjectTransformer $orderToSubscriberTransformer,
     OrderSubjectToSegmentSubjectTransformer $orderToSegmentTransformer,
+    SubscriberSubjectToWordPressUserSubjectTransformer $subscriberToWordPressUserTransformer,
     SomeoneSubscribesTrigger $someoneSubscribesTrigger,
     UserRegistrationTrigger $userRegistrationTrigger,
     SendEmailAction $sendEmailAction,
@@ -62,6 +67,7 @@ class MailPoetIntegration implements Integration {
     $this->subscriberSubject = $subscriberSubject;
     $this->orderToSubscriberTransformer = $orderToSubscriberTransformer;
     $this->orderToSegmentTransformer = $orderToSegmentTransformer;
+    $this->subscriberToWordPressUserTransformer = $subscriberToWordPressUserTransformer;
     $this->someoneSubscribesTrigger = $someoneSubscribesTrigger;
     $this->userRegistrationTrigger = $userRegistrationTrigger;
     $this->sendEmailAction = $sendEmailAction;
@@ -81,6 +87,7 @@ class MailPoetIntegration implements Integration {
     $registry->addAction($this->sendEmailAction);
     $registry->addSubjectTransformer($this->orderToSubscriberTransformer);
     $registry->addSubjectTransformer($this->orderToSegmentTransformer);
+    $registry->addSubjectTransformer($this->subscriberToWordPressUserTransformer);
 
     // sync step args (subject, preheader, etc.) to email settings
     $registry->onBeforeAutomationStepSave(
diff --git a/mailpoet/lib/Automation/Integrations/MailPoet/SubjectTransformers/SubscriberSubjectToWordPressUserSubjectTransformer.php b/mailpoet/lib/Automation/Integrations/MailPoet/SubjectTransformers/SubscriberSubjectToWordPressUserSubjectTransformer.php
new file mode 100644
index 0000000000..1d3f961233
--- /dev/null
+++ b/mailpoet/lib/Automation/Integrations/MailPoet/SubjectTransformers/SubscriberSubjectToWordPressUserSubjectTransformer.php
@@ -0,0 +1,40 @@
+<?php declare(strict_types = 1);
+
+namespace MailPoet\Automation\Integrations\MailPoet\SubjectTransformers;
+
+use MailPoet\Automation\Engine\Data\Subject;
+use MailPoet\Automation\Engine\Integration\SubjectTransformer;
+use MailPoet\Automation\Integrations\MailPoet\Subjects\SubscriberSubject;
+use MailPoet\Automation\Integrations\WordPress\Subjects\UserSubject;
+use MailPoet\Subscribers\SubscribersRepository;
+
+class SubscriberSubjectToWordPressUserSubjectTransformer implements SubjectTransformer {
+  /** @var SubscribersRepository */
+  private $subscribersRepository;
+
+  public function __construct(
+    SubscribersRepository $subscribersRepository
+  ) {
+    $this->subscribersRepository = $subscribersRepository;
+  }
+
+  public function accepts(): string {
+    return SubscriberSubject::KEY;
+  }
+
+  public function returns(): string {
+    return UserSubject::KEY;
+  }
+
+  public function transform(Subject $data): Subject {
+    if ($this->accepts() !== $data->getKey()) {
+      throw new \InvalidArgumentException('Invalid subject type');
+    }
+
+    $subscriber = $this->subscribersRepository->findOneById((int)$data->getArgs()['subscriber_id']);
+    if (!$subscriber) {
+      throw new \InvalidArgumentException('Subscriber not found');
+    }
+    return new Subject(UserSubject::KEY, ['user_id' => $subscriber->getWpUserId()]);
+  }
+}
diff --git a/mailpoet/lib/DI/ContainerConfigurator.php b/mailpoet/lib/DI/ContainerConfigurator.php
index 8f82471a9d..4315c45084 100644
--- a/mailpoet/lib/DI/ContainerConfigurator.php
+++ b/mailpoet/lib/DI/ContainerConfigurator.php
@@ -176,6 +176,7 @@ class ContainerConfigurator implements IContainerConfigurator {
     $container->autowire(\MailPoet\Automation\Integrations\MailPoet\Hooks\CreateAutomationRunHook::class)->setPublic(true);
     $container->autowire(\MailPoet\Automation\Integrations\MailPoet\SubjectTransformers\OrderSubjectToSubscriberSubjectTransformer::class)->setPublic(true)->setShared(false);
     $container->autowire(\MailPoet\Automation\Integrations\MailPoet\SubjectTransformers\OrderSubjectToSegmentSubjectTransformer::class)->setPublic(true)->setShared(false);
+    $container->autowire(\MailPoet\Automation\Integrations\MailPoet\SubjectTransformers\SubscriberSubjectToWordPressUserSubjectTransformer::class)->setPublic(true)->setShared(false);
 
     // Automation - WooCommerce integration
     $container->autowire(\MailPoet\Automation\Integrations\WooCommerce\ContextFactory::class)->setPublic(true);