diff --git a/assets/js/src/public.js b/assets/js/src/public.js
index d5ea37e133..7353e480c3 100644
--- a/assets/js/src/public.js
+++ b/assets/js/src/public.js
@@ -60,11 +60,22 @@ jQuery(function ($) { // eslint-disable-line func-names
           data: formData.data,
         })
           .fail(function handleFailedPost(response) {
-            form.find('.mailpoet_validate_error').html(
-              response.errors.map(function buildErrorMessage(error) {
-                return error.message;
-              }).join('<br />')
-            ).show();
+            if (
+              response.meta !== undefined
+                && response.meta.redirect_url !== undefined
+            ) {
+              // go to page
+              window.top.location.href = response.meta.redirect_url;
+            } else {
+              if (response.meta && response.meta.refresh_captcha) {
+                $('.mailpoet_captcha_update').click();
+              }
+              form.find('.mailpoet_validate_error').html(
+                response.errors.map(function buildErrorMessage(error) {
+                  return error.message;
+                }).join('<br />')
+              ).show();
+            }
           })
           .done(function handleRecaptcha(response) {
             if (window.grecaptcha && formData.recaptcha) {
@@ -83,6 +94,10 @@ jQuery(function ($) { // eslint-disable-line func-names
             } else {
               // display success message
               form.find('.mailpoet_validate_success').show();
+              // hide elements marked with a class
+              form.find('.mailpoet_form_hide_on_success').each(function hideOnSuccess() {
+                $(this).hide();
+              });
             }
 
             // reset form
@@ -109,5 +124,14 @@ jQuery(function ($) { // eslint-disable-line func-names
         return false;
       });
     });
+
+    $('.mailpoet_captcha_update').click(function updateCaptcha(e) {
+      var captcha = $('img.mailpoet_captcha');
+      var captchaSrc = captcha.attr('src');
+      var hashPos = captchaSrc.indexOf('#');
+      var newSrc = hashPos > 0 ? captchaSrc.substring(0, hashPos) : captchaSrc;
+      captcha.attr('src', newSrc + '#' + new Date().getTime());
+      e.preventDefault();
+    });
   });
 });
diff --git a/lib/API/JSON/API.php b/lib/API/JSON/API.php
index e1717a0026..5f9ec15bc6 100644
--- a/lib/API/JSON/API.php
+++ b/lib/API/JSON/API.php
@@ -3,6 +3,7 @@ namespace MailPoet\API\JSON;
 
 use MailPoet\Config\AccessControl;
 use MailPoet\Settings\SettingsController;
+use MailPoet\Subscription\Captcha;
 use MailPoetVendor\Psr\Container\ContainerInterface;
 use MailPoet\Util\Helpers;
 use MailPoet\Util\Security;
@@ -79,7 +80,7 @@ class API {
     $this->setRequestData($_POST);
 
     $ignoreToken = (
-      $this->settings->get('re_captcha.enabled') &&
+      $this->settings->get('captcha.type') != Captcha::TYPE_DISABLED &&
       $this->_request_endpoint === 'subscribers' &&
       $this->_request_method === 'subscribe'
     );
diff --git a/lib/API/JSON/v1/Subscribers.php b/lib/API/JSON/v1/Subscribers.php
index 21839eccf7..c7bec4eac2 100644
--- a/lib/API/JSON/v1/Subscribers.php
+++ b/lib/API/JSON/v1/Subscribers.php
@@ -18,7 +18,9 @@ use MailPoet\Settings\SettingsController;
 use MailPoet\Subscribers\RequiredCustomFieldValidator;
 use MailPoet\Subscribers\Source;
 use MailPoet\Subscribers\SubscriberActions;
+use MailPoet\Subscription\Captcha;
 use MailPoet\Subscription\Throttling as SubscriptionThrottling;
+use MailPoet\Subscription\Url as SubscriptionUrl;
 use MailPoet\WP\Functions as WPFunctions;
 
 if (!defined('ABSPATH')) exit;
@@ -46,6 +48,9 @@ class Subscribers extends APIEndpoint {
   /** @var Listing\Handler */
   private $listing_handler;
 
+  /** @var Captcha */
+  private $subscription_captcha;
+
   /** @var WPFunctions */
   private $wp;
 
@@ -58,6 +63,7 @@ class Subscribers extends APIEndpoint {
     SubscriberActions $subscriber_actions,
     RequiredCustomFieldValidator $required_custom_field_validator,
     Listing\Handler $listing_handler,
+    Captcha $subscription_captcha,
     WPFunctions $wp,
     SettingsController $settings
   ) {
@@ -66,6 +72,7 @@ class Subscribers extends APIEndpoint {
     $this->subscriber_actions = $subscriber_actions;
     $this->required_custom_field_validator = $required_custom_field_validator;
     $this->listing_handler = $listing_handler;
+    $this->subscription_captcha = $subscription_captcha;
     $this->wp = $wp;
     $this->settings = $settings;
   }
@@ -140,8 +147,6 @@ class Subscribers extends APIEndpoint {
     $form = Form::findOne($form_id);
     unset($data['form_id']);
 
-    $recaptcha = $this->settings->get('re_captcha');
-
     if (!$form instanceof Form) {
       return $this->badRequest([
         APIError::BAD_REQUEST => WPFunctions::get()->__('Please specify a valid form ID.', 'mailpoet'),
@@ -153,31 +158,17 @@ class Subscribers extends APIEndpoint {
       ]);
     }
 
-    if (!empty($recaptcha['enabled']) && empty($data['recaptcha'])) {
-      return $this->badRequest([
-        APIError::BAD_REQUEST => WPFunctions::get()->__('Please check the CAPTCHA.', 'mailpoet'),
-      ]);
-    }
+    $captcha = $this->settings->get('captcha');
 
-    if (!empty($recaptcha['enabled'])) {
-      $res = empty($data['recaptcha']) ? $data['recaptcha-no-js'] : $data['recaptcha'];
-      $res = WPFunctions::get()->wpRemotePost('https://www.google.com/recaptcha/api/siteverify', [
-        'body' => [
-          'secret' => $recaptcha['secret_token'],
-          'response' => $res,
-        ],
-      ]);
-      if (is_wp_error($res)) {
-        return $this->badRequest([
-          APIError::BAD_REQUEST => WPFunctions::get()->__('Error while validating the CAPTCHA.', 'mailpoet'),
-        ]);
-      }
-      $res = json_decode(wp_remote_retrieve_body($res));
-      if (empty($res->success)) {
-        return $this->badRequest([
-          APIError::BAD_REQUEST => WPFunctions::get()->__('Error while validating the CAPTCHA.', 'mailpoet'),
-        ]);
+    if (!empty($captcha['type']) && $captcha['type'] === Captcha::TYPE_BUILTIN) {
+      if (empty($data['captcha'])) {
+        // Save form data to session
+        $_SESSION[Captcha::SESSION_FORM_KEY] = array_merge($data, ['form_id' => $form_id]);
+      } elseif (!empty($_SESSION[Captcha::SESSION_FORM_KEY])) {
+        // Restore form data from session
+        $data = array_merge($_SESSION[Captcha::SESSION_FORM_KEY], ['captcha' => $data['captcha']]);
       }
+      // Otherwise use the post data
     }
 
     $data = $this->deobfuscateFormPayload($data);
@@ -201,6 +192,64 @@ class Subscribers extends APIEndpoint {
       ]);
     }
 
+    $is_builtin_captcha_required = false;
+    if (!empty($captcha['type']) && $captcha['type'] === Captcha::TYPE_BUILTIN) {
+      $is_builtin_captcha_required = $this->subscription_captcha->isRequired(isset($data['email']) ? $data['email'] : '');
+      if ($is_builtin_captcha_required && empty($data['captcha'])) {
+        $meta = [];
+        $meta['redirect_url'] = SubscriptionUrl::getCaptchaUrl();
+        return $this->badRequest([
+          APIError::BAD_REQUEST => WPFunctions::get()->__('Please check the CAPTCHA.', 'mailpoet'),
+        ], $meta);
+      }
+    }
+
+    if (!empty($captcha['type']) && $captcha['type'] === Captcha::TYPE_RECAPTCHA && empty($data['recaptcha'])) {
+      return $this->badRequest([
+        APIError::BAD_REQUEST => WPFunctions::get()->__('Please check the CAPTCHA.', 'mailpoet'),
+      ]);
+    }
+
+    if (!empty($captcha['type'])) {
+      if ($captcha['type'] === Captcha::TYPE_RECAPTCHA) {
+        $res = empty($data['recaptcha']) ? $data['recaptcha-no-js'] : $data['recaptcha'];
+        $res = WPFunctions::get()->wpRemotePost('https://www.google.com/recaptcha/api/siteverify', [
+          'body' => [
+            'secret' => $captcha['recaptcha_secret_token'],
+            'response' => $res,
+          ],
+        ]);
+        if (is_wp_error($res)) {
+          return $this->badRequest([
+            APIError::BAD_REQUEST => WPFunctions::get()->__('Error while validating the CAPTCHA.', 'mailpoet'),
+          ]);
+        }
+        $res = json_decode(wp_remote_retrieve_body($res));
+        if (empty($res->success)) {
+          return $this->badRequest([
+            APIError::BAD_REQUEST => WPFunctions::get()->__('Error while validating the CAPTCHA.', 'mailpoet'),
+          ]);
+        }
+      } elseif ($captcha['type'] === Captcha::TYPE_BUILTIN && $is_builtin_captcha_required) {
+        if (empty($_SESSION[Captcha::SESSION_KEY])) {
+          return $this->badRequest([
+            APIError::BAD_REQUEST => WPFunctions::get()->__('Please regenerate the CAPTCHA.', 'mailpoet'),
+          ]);
+        } elseif (!hash_equals(strtolower($data['captcha']), $_SESSION[Captcha::SESSION_KEY])) {
+          $_SESSION[Captcha::SESSION_KEY] = null;
+          $meta = [];
+          $meta['refresh_captcha'] = true;
+          return $this->badRequest([
+            APIError::BAD_REQUEST => WPFunctions::get()->__('The characters entered do not match with the previous captcha.', 'mailpoet'),
+          ], $meta);
+        } else {
+          // Captcha has been verified, invalidate the session vars
+          $_SESSION[Captcha::SESSION_KEY] = null;
+          $_SESSION[Captcha::SESSION_FORM_KEY] = null;
+        }
+      }
+    }
+
     // only accept fields defined in the form
     $form_fields = $form->getFieldList();
     $data = array_intersect_key($data, array_flip($form_fields));
diff --git a/lib/Config/Initializer.php b/lib/Config/Initializer.php
index ee6b4aae30..408f8658dd 100644
--- a/lib/Config/Initializer.php
+++ b/lib/Config/Initializer.php
@@ -179,6 +179,7 @@ class Initializer {
 
   function initialize() {
     try {
+      $this->setupSession();
       $this->maybeDbUpdate();
       $this->setupInstaller();
       $this->setupUpdater();
@@ -207,6 +208,11 @@ class Initializer {
     define(self::INITIALIZED, true);
   }
 
+  function setupSession() {
+    $session = new Session;
+    $session->init();
+  }
+
   function maybeDbUpdate() {
     try {
       $current_db_version = $this->settings->get('db_version');
diff --git a/lib/Config/Populator.php b/lib/Config/Populator.php
index 7e54c2f737..8391a41a34 100644
--- a/lib/Config/Populator.php
+++ b/lib/Config/Populator.php
@@ -177,6 +177,9 @@ class Populator {
         'confirmation' => $mailpoet_page_id,
         'captcha' => $mailpoet_page_id,
       ]);
+    } elseif (empty($subscription['captcha'])) {
+      // For existing installations
+      $this->settings->set('subscription.pages', array_merge($subscription, ['captcha' => $mailpoet_page_id]));
     }
   }
 
diff --git a/lib/Config/Session.php b/lib/Config/Session.php
new file mode 100644
index 0000000000..1effb360be
--- /dev/null
+++ b/lib/Config/Session.php
@@ -0,0 +1,13 @@
+<?php
+
+namespace MailPoet\Config;
+
+if (!defined('ABSPATH')) exit;
+
+class Session {
+  function init() {
+    if (!session_id()) {
+      return session_start();
+    }
+  }
+}
diff --git a/lib/DI/ContainerConfigurator.php b/lib/DI/ContainerConfigurator.php
index aad72846b6..8ba6d5d88d 100644
--- a/lib/DI/ContainerConfigurator.php
+++ b/lib/DI/ContainerConfigurator.php
@@ -145,6 +145,7 @@ class ContainerConfigurator implements IContainerConfigurator {
     // User Flags
     $container->autowire(\MailPoet\Settings\UserFlagsController::class);
     // Subscription
+    $container->autowire(\MailPoet\Subscription\Captcha::class)->setPublic(true);
     $container->autowire(\MailPoet\Subscription\Comment::class)->setPublic(true);
     $container->autowire(\MailPoet\Subscription\Form::class)->setPublic(true);
     $container->autowire(\MailPoet\Subscription\Manage::class)->setPublic(true);
diff --git a/lib/Subscription/Captcha.php b/lib/Subscription/Captcha.php
index 2e1d2ca3d4..c0fb1ec0ef 100644
--- a/lib/Subscription/Captcha.php
+++ b/lib/Subscription/Captcha.php
@@ -2,6 +2,10 @@
 
 namespace MailPoet\Subscription;
 
+use MailPoet\Models\Subscriber;
+use MailPoet\Models\SubscriberIP;
+use MailPoet\Util\Helpers;
+use MailPoet\WP\Functions as WPFunctions;
 use MailPoetVendor\Gregwar\Captcha\CaptchaBuilder;
 
 class Captcha {
@@ -12,11 +16,57 @@ class Captcha {
   const SESSION_KEY = 'mailpoet_captcha';
   const SESSION_FORM_KEY = 'mailpoet_captcha_form';
 
+  /** @var WPFunctions */
+  private $wp;
+
+  function __construct(WPFunctions $wp = null) {
+    if ($wp === null) {
+      $wp = new WPFunctions;
+    }
+    $this->wp = $wp;
+  }
+
   function isSupported() {
     return extension_loaded('gd') && function_exists('imagettftext');
   }
 
-  function renderImage($width = null, $height = null) {
+  function isRequired($subscriber_email = null) {
+    if ($this->wp->isUserLoggedIn()) {
+      return false;
+    }
+
+    // Check limits per recipient
+    $subscription_captcha_recipient_limit = $this->wp->applyFilters('mailpoet_subscription_captcha_recipient_limit', 1);
+    if ($subscriber_email) {
+      $subscriber = Subscriber::where('email', $subscriber_email)->findOne();
+      if ($subscriber instanceof Subscriber
+        && $subscriber->count_confirmations >= $subscription_captcha_recipient_limit
+      ) {
+        return true;
+      }
+    }
+
+    // Check limits per IP address
+    $subscription_captcha_window = $this->wp->applyFilters('mailpoet_subscription_captcha_window', MONTH_IN_SECONDS);
+
+    $subscriber_ip = Helpers::getIP();
+
+    if (!empty($subscriber_ip)) {
+      $subscription_count = SubscriberIP::where('ip', $subscriber_ip)
+        ->whereRaw(
+          '(`created_at` >= NOW() - INTERVAL ? SECOND)',
+          [(int)$subscription_captcha_window]
+        )->count();
+
+      if ($subscription_count > 0) {
+        return true;
+      }
+    }
+
+    return false;
+  }
+
+  function renderImage($width = null, $height = null, $return = false) {
     if (!$this->isSupported()) {
       return false;
     }
@@ -36,6 +86,10 @@ class Captcha {
 
     $_SESSION[self::SESSION_KEY] = $builder->getPhrase();
 
+    if ($return) {
+      return $builder->get();
+    }
+
     header('Content-Type: image/jpeg');
     $builder->output();
     exit;
diff --git a/lib/Subscription/Form.php b/lib/Subscription/Form.php
index 2d4309d0f8..45b0801d81 100644
--- a/lib/Subscription/Form.php
+++ b/lib/Subscription/Form.php
@@ -25,7 +25,9 @@ class Form {
     $form_id = (!empty($request_data['data']['form_id'])) ? (int)$request_data['data']['form_id'] : false;
     $response = $this->api->processRoute();
     if ($response->status !== APIResponse::STATUS_OK) {
-      return $this->url_helper->redirectBack(
+      return (isset($response->meta['redirect_url'])) ?
+      $this->url_helper->redirectTo($response->meta['redirect_url']) :
+      $this->url_helper->redirectBack(
         [
           'mailpoet_error' => ($form_id) ? $form_id : true,
           'mailpoet_success' => null,
diff --git a/lib/Subscription/Pages.php b/lib/Subscription/Pages.php
index f62d6ee4a1..15322c3b01 100644
--- a/lib/Subscription/Pages.php
+++ b/lib/Subscription/Pages.php
@@ -2,6 +2,7 @@
 
 namespace MailPoet\Subscription;
 
+use MailPoet\Models\Form as FormModel;
 use MailPoet\Models\Subscriber;
 use MailPoet\Models\SubscriberSegment;
 use MailPoet\Models\CustomField;
@@ -290,6 +291,8 @@ class Pages {
     );
 
     $form_id = isset($_SESSION[Captcha::SESSION_FORM_KEY]['form_id']) ? (int)$_SESSION[Captcha::SESSION_FORM_KEY]['form_id'] : 0;
+    $form_model = FormModel::findOne($form_id);
+    $form_model = $form_model->asArray();
 
     $form_html = '<form method="POST" ' .
       'action="' . admin_url('admin-post.php?action=mailpoet_subscription_form') . '" ' .
@@ -315,7 +318,7 @@ class Pages {
     $form_html .= FormRenderer::renderBlocks($form, $honeypot = false);
     $form_html .= '</div>';
     $form_html .= '<div class="mailpoet_message">';
-    $form_html .= '<p class="mailpoet_validate_success" style="display:none;">Check your inbox or spam folder to confirm your subscription.</p>';
+    $form_html .= '<p class="mailpoet_validate_success" style="display:none;">' . $form_model['settings']['success_message'] . '</p>';
     $form_html .= '<p class="mailpoet_validate_error" style="display:none;"></p>';
     $form_html .= '</div>';
     $form_html .= '</form>';
diff --git a/lib/Subscription/Throttling.php b/lib/Subscription/Throttling.php
index b0021e9ae2..1104283ec5 100644
--- a/lib/Subscription/Throttling.php
+++ b/lib/Subscription/Throttling.php
@@ -14,7 +14,6 @@ class Throttling {
     $subscription_limit_base = $wp->applyFilters('mailpoet_subscription_limit_base', MINUTE_IN_SECONDS);
 
     $subscriber_ip = Helpers::getIP();
-    $wp = new WPFunctions;
 
     if ($subscription_limit_enabled && !$wp->isUserLoggedIn()) {
       if (!empty($subscriber_ip)) {
@@ -43,12 +42,14 @@ class Throttling {
     $ip->ip = $subscriber_ip;
     $ip->save();
 
-    self::purge($subscription_limit_window);
+    self::purge();
 
     return false;
   }
 
-  static function purge($interval) {
+  static function purge() {
+    $wp = new WPFunctions;
+    $interval = $wp->applyFilters('mailpoet_subscription_purge_window', MONTH_IN_SECONDS);
     return SubscriberIP::whereRaw(
       '(`created_at` < NOW() - INTERVAL ? SECOND)',
       [$interval]