core/lib/Drupal/Core/EventSubscriber/MaintenanceModeSubscriber.php | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/core/lib/Drupal/Core/EventSubscriber/MaintenanceModeSubscriber.php b/core/lib/Drupal/Core/EventSubscriber/MaintenanceModeSubscriber.php
index bdd05c7..a32fa71 100644
--- a/core/lib/Drupal/Core/EventSubscriber/MaintenanceModeSubscriber.php
+++ b/core/lib/Drupal/Core/EventSubscriber/MaintenanceModeSubscriber.php
@@ -98,6 +98,8 @@ public function __construct(MaintenanceModeInterface $maintenance_mode, ConfigFa
   public function onKernelRequestMaintenance(GetResponseEvent $event) {
     $route_match = RouteMatch::createFromRequest($event->getRequest());
     if ($this->maintenanceMode->applies($route_match)) {
+      // Don't cache maintenance mode pages.
+      \Drupal::service('page_cache_kill_switch')->trigger();
       if (!$this->maintenanceMode->exempt($this->account)) {
         // Deliver the 503 page if the site is in maintenance mode and the
         // logged in user is not allowed to bypass it.