diff --git a/mailpoet/lib/Segments/WP.php b/mailpoet/lib/Segments/WP.php
index 016e27d204..9e515cffd8 100644
--- a/mailpoet/lib/Segments/WP.php
+++ b/mailpoet/lib/Segments/WP.php
@@ -219,6 +219,7 @@ class WP {
     $this->updateFirstNameIfMissing();
     $this->insertUsersToSegment();
     $this->removeOrphanedSubscribers();
+    $this->subscribersRepository->invalidateTotalSubscribersCache();
 
     return true;
   }
diff --git a/mailpoet/lib/Segments/WooCommerce.php b/mailpoet/lib/Segments/WooCommerce.php
index 4aadc42554..803011f6fb 100644
--- a/mailpoet/lib/Segments/WooCommerce.php
+++ b/mailpoet/lib/Segments/WooCommerce.php
@@ -188,6 +188,7 @@ class WooCommerce {
       $this->updateGlobalStatus();
     }
 
+    $this->subscribersRepository->invalidateTotalSubscribersCache();
     return $lastCheckedOrderId;
   }
 
diff --git a/mailpoet/lib/Subscribers/ImportExport/Import/Import.php b/mailpoet/lib/Subscribers/ImportExport/Import/Import.php
index 4f5c73b106..7d82e6bbb8 100644
--- a/mailpoet/lib/Subscribers/ImportExport/Import/Import.php
+++ b/mailpoet/lib/Subscribers/ImportExport/Import/Import.php
@@ -512,6 +512,8 @@ class Import {
       }
     }
     if (empty($createdOrUpdatedSubscribers)) return null;
+
+    $this->subscriberRepository->invalidateTotalSubscribersCache();
     $createdOrUpdatedSubscribersIds = array_column($createdOrUpdatedSubscribers, 'id');
     if ($subscribersCustomFields) {
       $this->createOrUpdateCustomFields(
@@ -588,7 +590,9 @@ class Import {
    * @return array
    */
   public function synchronizeWPUsers(array $wpUsers): array {
-    return array_map([$this->wpSegment, 'synchronizeUser'], $wpUsers);
+    $users = array_map([$this->wpSegment, 'synchronizeUser'], $wpUsers);
+    $this->subscriberRepository->invalidateTotalSubscribersCache();
+    return $users;
   }
 
   public function addSubscribersToSegments(array $subscribersIds, array $segmentsIds): void {
diff --git a/mailpoet/lib/Subscribers/SubscribersRepository.php b/mailpoet/lib/Subscribers/SubscribersRepository.php
index 671d361fa6..3e9b2c401b 100644
--- a/mailpoet/lib/Subscribers/SubscribersRepository.php
+++ b/mailpoet/lib/Subscribers/SubscribersRepository.php
@@ -7,6 +7,7 @@ use MailPoet\Entities\SegmentEntity;
 use MailPoet\Entities\SubscriberCustomFieldEntity;
 use MailPoet\Entities\SubscriberEntity;
 use MailPoet\Entities\SubscriberSegmentEntity;
+use MailPoet\Util\License\Features\Subscribers;
 use MailPoet\WP\Functions as WPFunctions;
 use MailPoetVendor\Carbon\Carbon;
 use MailPoetVendor\Carbon\CarbonImmutable;
@@ -41,10 +42,7 @@ class SubscribersRepository extends Repository {
     return SubscriberEntity::class;
   }
 
-  /**
-   * @return int
-   */
-  public function getTotalSubscribers() {
+  public function getTotalSubscribers(): int {
     $query = $this->entityManager
       ->createQueryBuilder()
       ->select('count(n.id)')
@@ -59,6 +57,10 @@ class SubscribersRepository extends Repository {
     return (int)$query->getSingleScalarResult();
   }
 
+  public function invalidateTotalSubscribersCache(): void {
+    $this->wp->deleteTransient(Subscribers::SUBSCRIBERS_COUNT_CACHE_KEY);
+  }
+
   public function findBySegment(int $segmentId): array {
     return $this->entityManager
     ->createQueryBuilder()
@@ -116,6 +118,7 @@ class SubscribersRepository extends Repository {
       ->setParameter('ids', $ids)
       ->getQuery()->execute();
 
+    $this->invalidateTotalSubscribersCache();
     return count($ids);
   }
 
@@ -135,6 +138,7 @@ class SubscribersRepository extends Repository {
       ->setParameter('ids', $ids)
       ->getQuery()->execute();
 
+    $this->invalidateTotalSubscribersCache();
     return count($ids);
   }
 
@@ -171,6 +175,7 @@ class SubscribersRepository extends Repository {
         ->getQuery()->execute();
     });
 
+    $this->invalidateTotalSubscribersCache();
     return $count;
   }
 
@@ -282,6 +287,7 @@ class SubscribersRepository extends Repository {
       ->setParameter('ids', $ids)
       ->getQuery()->execute();
 
+    $this->invalidateTotalSubscribersCache();
     return count($ids);
   }
 
diff --git a/mailpoet/lib/Util/License/Features/Subscribers.php b/mailpoet/lib/Util/License/Features/Subscribers.php
index 2400cc3471..48e230313c 100644
--- a/mailpoet/lib/Util/License/Features/Subscribers.php
+++ b/mailpoet/lib/Util/License/Features/Subscribers.php
@@ -5,6 +5,7 @@ namespace MailPoet\Util\License\Features;
 use MailPoet\Services\Bridge;
 use MailPoet\Settings\SettingsController;
 use MailPoet\Subscribers\SubscribersRepository;
+use MailPoet\WP\Functions as WPFunctions;
 
 class Subscribers {
   const SUBSCRIBERS_OLD_LIMIT = 2000;
@@ -18,6 +19,9 @@ class Subscribers {
   const PREMIUM_EMAIL_VOLUME_LIMIT_SETTING_KEY = 'premium.premium_key_state.data.email_volume_limit';
   const PREMIUM_EMAILS_SENT_SETTING_KEY = 'premium.premium_key_state.data.emails_sent';
   const PREMIUM_SUPPORT_SETTING_KEY = 'premium.premium_key_state.data.support_tier';
+  const SUBSCRIBERS_COUNT_CACHE_KEY = 'mailpoet_subscribers_count';
+  const SUBSCRIBERS_COUNT_CACHE_EXPIRATION_MINUTES = 60;
+  const SUBSCRIBERS_COUNT_CACHE_MIN_VALUE = 1000;
 
   /** @var SettingsController */
   private $settings;
@@ -25,15 +29,20 @@ class Subscribers {
   /** @var SubscribersRepository */
   private $subscribersRepository;
 
+  /** @var WPFunctions */
+  private $wp;
+
   public function __construct(
     SettingsController $settings,
-    SubscribersRepository $subscribersRepository
+    SubscribersRepository $subscribersRepository,
+    WPFunctions $wp
   ) {
     $this->settings = $settings;
     $this->subscribersRepository = $subscribersRepository;
+    $this->wp = $wp;
   }
 
-  public function check() {
+  public function check(): bool {
     $limit = $this->getSubscribersLimit();
     if ($limit === false) return false;
     $subscribersCount = $this->getSubscribersCount();
@@ -49,11 +58,21 @@ class Subscribers {
     return $emailsSent > $emailVolumeLimit;
   }
 
-  public function getSubscribersCount() {
-    return $this->subscribersRepository->getTotalSubscribers();
+  public function getSubscribersCount(): int {
+    $count = $this->wp->getTransient(self::SUBSCRIBERS_COUNT_CACHE_KEY);
+    if (is_numeric($count)) {
+      return (int)$count;
+    }
+    $count = $this->subscribersRepository->getTotalSubscribers();
+
+    // cache only when number of subscribers exceeds minimum value
+    if ($count > self::SUBSCRIBERS_COUNT_CACHE_MIN_VALUE) {
+      $this->wp->setTransient(self::SUBSCRIBERS_COUNT_CACHE_KEY, $count, self::SUBSCRIBERS_COUNT_CACHE_EXPIRATION_MINUTES * 60);
+    }
+    return $count;
   }
 
-  public function hasValidApiKey() {
+  public function hasValidApiKey(): bool {
     return $this->hasValidMssKey() || $this->hasValidPremiumKey();
   }
 
diff --git a/mailpoet/tests/integration/Util/License/Features/SubscribersTest.php b/mailpoet/tests/integration/Util/License/Features/SubscribersTest.php
new file mode 100644
index 0000000000..9352e05026
--- /dev/null
+++ b/mailpoet/tests/integration/Util/License/Features/SubscribersTest.php
@@ -0,0 +1,137 @@
+<?php declare(strict_types = 1);
+
+namespace MailPoet\Subscribers;
+
+use MailPoet\Entities\SubscriberEntity;
+use MailPoet\WP\Functions as WPFunctions;
+use MailPoet\Util\License\Features\Subscribers;
+use Codeception\Stub;
+
+class SubscribersTest extends \MailPoetTest {
+  /** @var Subscribers */
+  private $subscribers;
+
+  /** @var SubscribersRepository */
+  private $subscribersRepository;
+
+  /** @var WPFunctions */
+  private $wp;
+
+  public function _before() {
+    parent::_before();
+    $this->subscribers = $this->diContainer->get(Subscribers::class);
+    $this->subscribersRepository = $this->diContainer->get(SubscribersRepository::class);
+    $this->wp = $this->diContainer->get(WPFunctions::class);
+    $this->wp->deleteTransient(Subscribers::SUBSCRIBERS_COUNT_CACHE_KEY);
+  }
+
+  public function testItComputesSubscribersCount() {
+    // no subscribers
+    $count = $this->subscribers->getSubscribersCount();
+    expect($count)->same(0);
+
+    // create some subscribers (unconfirmed, subscribed, and inactive should be counted)
+    $this->createSubscriber('unconfirmed@fake.loc', SubscriberEntity::STATUS_UNCONFIRMED);
+    $this->createSubscriber('subscribed@fake.loc', SubscriberEntity::STATUS_SUBSCRIBED);
+    $this->createSubscriber('inactive@fake.loc', SubscriberEntity::STATUS_INACTIVE);
+
+    // check count
+    $count = $this->subscribers->getSubscribersCount();
+    expect($count)->same(3);
+
+    // add more subscribers (bounced, unsubscribed, and trashed should not be counted)
+    $this->createSubscriber('bounced@fake.loc', SubscriberEntity::STATUS_BOUNCED);
+    $this->createSubscriber('unsubscribed@fake.loc', SubscriberEntity::STATUS_UNSUBSCRIBED);
+    $trashed = $this->createSubscriber('trashed@fake.loc', SubscriberEntity::STATUS_SUBSCRIBED);
+    $trashed->setDeletedAt(new \DateTimeImmutable());
+    $this->subscribersRepository->flush();
+
+    // check count
+    $count = $this->subscribers->getSubscribersCount();
+    expect($count)->same(3);
+  }
+
+  public function testItDoesntCacheSubscribersCountForLowValues() {
+    // no subscribers
+    $count = $this->subscribers->getSubscribersCount();
+    expect($count)->same(0);
+
+    // add subscriber
+    $this->createSubscriber('one@fake.loc', SubscriberEntity::STATUS_SUBSCRIBED);
+    $count = $this->subscribers->getSubscribersCount();
+    expect($count)->same(1);
+
+    // add another subscriber (count updates without cache purging)
+    $this->createSubscriber('two@fake.loc', SubscriberEntity::STATUS_SUBSCRIBED);
+    $count = $this->subscribers->getSubscribersCount();
+    expect($count)->same(2);
+  }
+
+  public function testItCachesSubscribersCountForHighValues() {
+    $subscribers = $this->getServiceWithOverrides(Subscribers::class, [
+      'subscribersRepository' => Stub::make(SubscribersRepository::class, [
+        'getTotalSubscribers' => 123456,
+      ]),
+    ]);
+
+    $count = $subscribers->getSubscribersCount();
+    expect($count)->same(123456);
+
+    $subscribers = $this->getServiceWithOverrides(Subscribers::class, [
+      'subscribersRepository' => Stub::make(SubscribersRepository::class, [
+        'getTotalSubscribers' => 999999,
+      ]),
+    ]);
+
+    // check count (cached value)
+    $count = $subscribers->getSubscribersCount();
+    expect($count)->same(123456);
+
+    // check count (uncached value)
+    $this->wp->deleteTransient(Subscribers::SUBSCRIBERS_COUNT_CACHE_KEY);
+    $count = $subscribers->getSubscribersCount();
+    expect($count)->same(999999);
+  }
+
+  public function testItInvalidatesSubscribersCountCache() {
+    $subscribers = $this->getServiceWithOverrides(Subscribers::class, [
+      'subscribersRepository' => Stub::make(SubscribersRepository::class, [
+        'getTotalSubscribers' => 123456,
+      ]),
+    ]);
+    $subscribers->getSubscribersCount();
+
+    $subscribers = $this->getServiceWithOverrides(Subscribers::class, [
+      'subscribersRepository' => Stub::make(SubscribersRepository::class, [
+        'getTotalSubscribers' => 999999,
+      ]),
+    ]);
+
+    // check count (cached value)
+    $count = $subscribers->getSubscribersCount();
+    expect($count)->same(123456);
+
+    // modify timestamp, check count (-> uncached value)
+    $this->wp->updateOption(
+      '_transient_timeout_' . Subscribers::SUBSCRIBERS_COUNT_CACHE_KEY,
+      $this->wp->currentTime('timestamp') - 1
+    );
+    $count = $subscribers->getSubscribersCount();
+    expect($count)->same(999999);
+  }
+
+  public function _after() {
+    parent::_after();
+    $this->truncateEntity(SubscriberEntity::class);
+    $this->wp->deleteTransient(Subscribers::SUBSCRIBERS_COUNT_CACHE_KEY);
+  }
+
+  private function createSubscriber(string $email, string $status): SubscriberEntity {
+    $subscriber = new SubscriberEntity();
+    $subscriber->setEmail($email);
+    $subscriber->setStatus($status);
+    $this->subscribersRepository->persist($subscriber);
+    $this->subscribersRepository->flush();
+    return $subscriber;
+  }
+}
diff --git a/mailpoet/tests/unit/Util/License/Features/SubscribersTest.php b/mailpoet/tests/unit/Util/License/Features/SubscribersTest.php
index 34e78b9646..0ad61bd953 100644
--- a/mailpoet/tests/unit/Util/License/Features/SubscribersTest.php
+++ b/mailpoet/tests/unit/Util/License/Features/SubscribersTest.php
@@ -6,6 +6,7 @@ use Codeception\Util\Stub;
 use MailPoet\Settings\SettingsController;
 use MailPoet\Subscribers\SubscribersRepository;
 use MailPoet\Util\License\Features\Subscribers as SubscribersFeature;
+use MailPoet\WP\Functions as WPFunctions;
 
 class SubscribersTest extends \MailPoetUnitTest {
   public function testCheckReturnsTrueIfOldUserReachedLimit() {
@@ -178,12 +179,18 @@ class SubscribersTest extends \MailPoetUnitTest {
         if ($name === SubscribersFeature::PREMIUM_SUPPORT_SETTING_KEY) return isset($specs['support_tier']) ? $specs['support_tier'] : 'free';
       },
     ]);
+
     $subscribersRepository = Stub::make(SubscribersRepository::class, [
       'getTotalSubscribers' => function() use($specs) {
         return $specs['subscribers_count'];
       },
     ]);
 
-    return new SubscribersFeature($settings, $subscribersRepository);
+    $wpFunctions = Stub::make(WPFunctions::class, [
+      'getTransient' => false,
+      'setTransient' => false,
+    ]);
+
+    return new SubscribersFeature($settings, $subscribersRepository, $wpFunctions);
   }
 }