diff --git a/lib/Config/Hooks.php b/lib/Config/Hooks.php
index bb63fcee03..a0ec6d25b4 100644
--- a/lib/Config/Hooks.php
+++ b/lib/Config/Hooks.php
@@ -8,6 +8,7 @@ use MailPoet\Subscription\Comment;
 use MailPoet\Subscription\Form;
 use MailPoet\Subscription\Registration;
 use MailPoet\Segments\WooCommerce as WooCommerceSegment;
+use MailPoet\WooCommerce\Subscription as WooCommerceSubscription;
 use MailPoet\WP\Functions as WPFunctions;
 
 class Hooks {
@@ -27,6 +28,9 @@ class Hooks {
   /** @var WPFunctions */
   private $wp;
 
+  /** @var WooCommerceSubscription */
+  private $woocommerce_subscription;
+
   /** @var WooCommerceSegment */
   private $woocommerce_segment;
 
@@ -39,6 +43,7 @@ class Hooks {
     Registration $subscription_registration,
     SettingsController $settings,
     WPFunctions $wp,
+    WooCommerceSubscription $woocommerce_subscription,
     WooCommerceSegment $woocommerce_segment,
     WooCommercePurchases $woocommerce_purchases
   ) {
@@ -47,6 +52,7 @@ class Hooks {
     $this->subscription_registration = $subscription_registration;
     $this->settings = $settings;
     $this->wp = $wp;
+    $this->woocommerce_subscription = $woocommerce_subscription;
     $this->woocommerce_segment = $woocommerce_segment;
     $this->woocommerce_purchases = $woocommerce_purchases;
   }
@@ -58,6 +64,7 @@ class Hooks {
     $this->setupImageSize();
     $this->setupListing();
     $this->setupSubscriptionEvents();
+    $this->setupWooCommerceSubscriptionEvents();
     $this->setupPostNotifications();
   }
 
@@ -149,6 +156,25 @@ class Hooks {
     );
   }
 
+  function setupWooCommerceSubscriptionEvents() {
+
+    $woocommerce = $this->settings->get('woocommerce', []);
+    // WooCommerce: subscribe on checkout
+    if (!empty($woocommerce['optin_on_checkout']['enabled'])) {
+      $this->wp->addAction(
+        'woocommerce_checkout_before_terms_and_conditions',
+        [$this->woocommerce_subscription, 'extendWooCommerceCheckoutForm']
+      );
+    }
+
+    $this->wp->addAction(
+      'woocommerce_checkout_update_order_meta',
+      [$this->woocommerce_subscription, 'subscribeOnCheckout'],
+      10, // this should execute after the WC sync call on the same hook
+      2
+    );
+  }
+
   function setupWPUsers() {
     // WP Users synchronization
     $this->wp->addAction(
diff --git a/lib/Config/Migrator.php b/lib/Config/Migrator.php
index 5fdcea3b6e..f57c5d9cad 100644
--- a/lib/Config/Migrator.php
+++ b/lib/Config/Migrator.php
@@ -202,7 +202,7 @@ class Migrator {
       'updated_at timestamp NOT NULL DEFAULT CURRENT_TIMESTAMP ON UPDATE CURRENT_TIMESTAMP,',
       'deleted_at timestamp NULL,',
       'unconfirmed_data longtext,',
-      "source enum('form','imported','administrator','api','wordpress_user','woocommerce_user','unknown') DEFAULT 'unknown',",
+      "source enum('form','imported','administrator','api','wordpress_user','woocommerce_user','woocommerce_checkout','unknown') DEFAULT 'unknown',",
       'count_confirmations int(11) unsigned NOT NULL DEFAULT 0,',
       'PRIMARY KEY  (id),',
       'UNIQUE KEY email (email),',
diff --git a/lib/DI/ContainerConfigurator.php b/lib/DI/ContainerConfigurator.php
index fb50228132..76f88e2a21 100644
--- a/lib/DI/ContainerConfigurator.php
+++ b/lib/DI/ContainerConfigurator.php
@@ -108,6 +108,7 @@ class ContainerConfigurator implements IContainerConfigurator {
     $container->autowire(\MailPoet\Newsletter\AutomatedLatestContent::class)->setPublic(true);
     // WooCommerce
     $container->autowire(\MailPoet\WooCommerce\Helper::class)->setPublic(true);
+    $container->autowire(\MailPoet\WooCommerce\Subscription::class)->setPublic(true);
     // WordPress
     $container->autowire(\MailPoet\WP\Functions::class)->setPublic(true);
     return $container;
diff --git a/lib/Models/SubscriberSegment.php b/lib/Models/SubscriberSegment.php
index 934ec7db6a..86260c969c 100644
--- a/lib/Models/SubscriberSegment.php
+++ b/lib/Models/SubscriberSegment.php
@@ -4,6 +4,13 @@ namespace MailPoet\Models;
 
 if (!defined('ABSPATH')) exit;
 
+/**
+ * @property int $id
+ * @property int $subscriber_id
+ * @property int $segment_id
+ * @property string $status
+ */
+
 class SubscriberSegment extends Model {
   public static $_table = MP_SUBSCRIBER_SEGMENT_TABLE;
 
diff --git a/lib/Subscribers/Source.php b/lib/Subscribers/Source.php
index 5c34964204..5e6e6ee552 100644
--- a/lib/Subscribers/Source.php
+++ b/lib/Subscribers/Source.php
@@ -12,6 +12,7 @@ class Source {
   const API = 'api';
   const WORDPRESS_USER = 'wordpress_user';
   const WOOCOMMERCE_USER = 'woocommerce_user';
+  const WOOCOMMERCE_CHECKOUT = 'woocommerce_checkout';
   const UNKNOWN = 'unknown';
 
   private static $allowed_sources = array(
@@ -21,6 +22,7 @@ class Source {
     Source::API,
     Source::WORDPRESS_USER,
     Source::WOOCOMMERCE_USER,
+    Source::WOOCOMMERCE_CHECKOUT,
     Source::UNKNOWN,
   );
 
diff --git a/lib/WooCommerce/Subscription.php b/lib/WooCommerce/Subscription.php
new file mode 100644
index 0000000000..87935d9323
--- /dev/null
+++ b/lib/WooCommerce/Subscription.php
@@ -0,0 +1,112 @@
+<?php
+namespace MailPoet\WooCommerce;
+
+use MailPoet\Models\Segment;
+use MailPoet\Models\Subscriber;
+use MailPoet\Models\SubscriberSegment;
+use MailPoet\Settings\SettingsController;
+use MailPoet\Subscribers\Source;
+use MailPoet\Util\Helpers;
+use MailPoet\WP\Functions as WPFunctions;
+
+class Subscription {
+  const CHECKOUT_OPTIN_INPUT_NAME = 'mailpoet_woocommerce_checkout_optin';
+  const OPTIN_ENABLED_SETTING_NAME = 'woocommerce.optin_on_checkout.enabled';
+  const OPTIN_MESSAGE_SETTING_NAME = 'woocommerce.optin_on_checkout.message';
+
+  /** @var SettingsController */
+  private $settings;
+
+  /** @var WPFunctions */
+  private $wp;
+
+  function __construct(
+    SettingsController $settings,
+    WPFunctions $wp
+  ) {
+    $this->settings = $settings;
+    $this->wp = $wp;
+  }
+
+  function extendWooCommerceCheckoutForm() {
+    $input_name = self::CHECKOUT_OPTIN_INPUT_NAME;
+    $checked = $this->isCurrentUserSubscribed();
+    $label_string = $this->settings->get(self::OPTIN_MESSAGE_SETTING_NAME);
+    $template = $this->wp->applyFilters(
+      'mailpoet_woocommerce_checkout_optin_template',
+      $this->getSubscriptionField($input_name, $checked, $label_string),
+      $input_name,
+      $checked,
+      $label_string
+    );
+    echo $template;
+  }
+
+  private function getSubscriptionField($input_name, $checked, $label_string) {
+    return '<p class="form-row">
+      <label class="woocommerce-form__label woocommerce-form__label-for-checkbox checkbox">
+      <input type="checkbox" class="woocommerce-form__input woocommerce-form__input-checkbox input-checkbox" name="'.$this->wp->escAttr($input_name).'" id="'.$this->wp->escAttr($input_name).'" ' . ($checked ? 'checked' : '') . ' />
+        <span class="woocommerce-terms-and-conditions-checkbox-text">' . $this->wp->escHtml($label_string) . '</label>
+    </p>';
+  }
+
+  private function isCurrentUserSubscribed() {
+    $subscriber = Subscriber::getCurrentWPUser();
+    if ($subscriber instanceof Subscriber) {
+      $wc_segment = Segment::getWooCommerceSegment();
+      $subscriber_segment = SubscriberSegment::where('subscriber_id', $subscriber->id)
+        ->where('segment_id', $wc_segment->id)
+        ->findOne();
+      if ($subscriber_segment instanceof SubscriberSegment
+        && $subscriber_segment->status === Subscriber::STATUS_SUBSCRIBED
+      ) {
+        return true;
+      }
+    }
+    return false;
+  }
+
+  function subscribeOnCheckout($order_id, $data) {
+    if (empty($data['billing_email'])) {
+      // no email in posted order data
+      return null;
+    }
+
+    $subscriber = Subscriber::where('email', $data['billing_email'])
+      ->where('is_woocommerce_user', 1)
+      ->findOne();
+    if (!$subscriber) {
+      // no subscriber: WooCommerce sync didn't work
+      return null;
+    }
+
+    $checkout_optin_enabled = (bool)$this->settings->get(self::OPTIN_ENABLED_SETTING_NAME);
+    $wc_segment = Segment::getWooCommerceSegment();
+
+    if ($checkout_optin_enabled) {
+      if (!empty($_POST[self::CHECKOUT_OPTIN_INPUT_NAME])) {
+        // checkbox is checked
+        $subscriber->source = Source::WOOCOMMERCE_CHECKOUT;
+        $subscriber->status = Subscriber::STATUS_SUBSCRIBED;
+        if (empty($subscriber->confirmed_ip) && empty($subscriber->confirmed_at)) {
+          $subscriber->confirmed_ip = Helpers::getIP();
+          $subscriber->setExpr('confirmed_at', 'NOW()');
+        }
+        $subscriber->save();
+
+        SubscriberSegment::subscribeToSegments(
+          $subscriber,
+          array($wc_segment->id)
+        );
+        return true;
+      }
+    }
+
+    // Opt-in is disabled or checkbox is unchecked
+    SubscriberSegment::unsubscribeFromSegments(
+      $subscriber,
+      array($wc_segment->id)
+    );
+    return false;
+  }
+}