diff --git a/src/Entity/Redirect.php b/src/Entity/Redirect.php
index c1796c1f..35f572d2 100644
--- a/src/Entity/Redirect.php
+++ b/src/Entity/Redirect.php
@@ -8,6 +8,9 @@
 use Drupal\Core\Entity\EntityStorageInterface;
 use Drupal\Core\Entity\EntityTypeInterface;
 use Drupal\Core\Field\BaseFieldDefinition;
+use Drupal\Core\Language\Language;
+use Drupal\Core\Language\LanguageDefault;
+use Drupal\Core\Language\LanguageInterface;
 use Drupal\link\LinkItemInterface;

 /**
@@ -85,9 +88,25 @@ public static function preCreate(EntityStorageInterface $storage_controller, arr
    * {@inheritdoc}
    */
   public function preSave(EntityStorageInterface $storage_controller) {
-    // Get the language code directly from the field as language() might not
-    // be up to date if the language was just changed.
-    $this->set('hash', Redirect::generateHash($this->redirect_source->path, (array) $this->redirect_source->query, $this->get('language')->value));
+    $path = $this->redirect_source->path;
+
+    // Get the language code directly from the field as language() might not be
+    // up to date if the language was just changed.
+    $redirect_language = $this->get('language')->value;
+
+    // Pass the path through the alias manager to convert it to the the alias's
+    // source. If it is not an alias the original value will be returned. Check
+    // for the Redirect's language, then language not specified and finally the
+    // default language for path aliases. We have to try multiple languages as
+    // there is no way to determine what the "correct" alias language might be
+    // without checking all options.
+    /** @var \Drupal\Core\Path\AliasManagerInterface $path_alias_manager */
+    $path_alias_manager = \Drupal::service('path.alias_manager');
+    if (!\Drupal::service('module_handler')->moduleExists('language')) {
+      $redirect_language = \Drupal::languageManager()->getCurrentLanguage()->getId();
+    }
+    $path = ltrim($path_alias_manager->getPathByAlias('/' . $path, $redirect_language), '/');
+    $this->set('hash', Redirect::generateHash($path, (array) $this->redirect_source->query, $redirect_language));
   }

   /**
diff --git a/src/EventSubscriber/RedirectRequestSubscriber.php b/src/EventSubscriber/RedirectRequestSubscriber.php
index 48fafc2d..e1672b4e 100644
--- a/src/EventSubscriber/RedirectRequestSubscriber.php
+++ b/src/EventSubscriber/RedirectRequestSubscriber.php
@@ -163,10 +163,21 @@ public function onKernelRequestCheckRedirect(GetResponseEvent $event) {
       if ($this->config->get('passthrough_querystring')) {
         $url->setOption('query', (array) $url->getOption('query') + $request_query);
       }
+
+      // Redirects to path aliases are stored and searched for using the alias's
+      // source (/node/123 vs /foo-bar-path). This can cause redirect loops
+      // because the path processor above may have converted a path alias to a
+      // path source (/foo-bar-path => /node/123) which will trigger a redirect
+      // on the path's valid alias.
+      $redirect_url = $url->setAbsolute()->toString();
+      if ($redirect_url === ($request->getSchemeAndHttpHost() . $request->getRequestUri())) {
+        return;
+      }
+
       $headers = [
         'X-Redirect-ID' => $redirect->id(),
       ];
-      $response = new TrustedRedirectResponse($url->setAbsolute()->toString(), $redirect->getStatusCode(), $headers);
+      $response = new TrustedRedirectResponse($redirect_url, $redirect->getStatusCode(), $headers);
       $response->addCacheableDependency($redirect);
       $event->setResponse($response);
     }
diff --git a/src/Form/RedirectForm.php b/src/Form/RedirectForm.php
index 1b4f4534..3dd7d032 100644
--- a/src/Form/RedirectForm.php
+++ b/src/Form/RedirectForm.php
@@ -54,7 +54,7 @@ protected function prepareEntity() {
         }
       }

-      $redirect->setLanguage($this->getRequest()->get('language') ? $this->getRequest()->get('language') : Language::LANGCODE_NOT_SPECIFIED);
+      $redirect->setLanguage($this->getRequest()->get('language') ? $this->getRequest()->get('language') : \Drupal::languageManager()->getCurrentLanguage()->getId());
     }
   }

@@ -124,18 +124,14 @@ public function validateForm(array &$form, FormStateInterface $form_state) {
       // Do nothing, we want to only compare the resulting URLs.
     }

-    $parsed_url = UrlHelper::parse(trim($source['path']));
-    $path = isset($parsed_url['path']) ? $parsed_url['path'] : NULL;
-    $query = isset($parsed_url['query']) ? $parsed_url['query'] : NULL;
-    $hash = Redirect::generateHash($path, $query, $form_state->getValue('language')[0]['value']);
-
     // Search for duplicate.
-    $redirects = \Drupal::entityTypeManager()
-      ->getStorage('redirect')
-      ->loadByProperties(['hash' => $hash]);
+    $parsed_url = UrlHelper::parse(trim($source['path']));
+    $path = isset($parsed_url['path']) ? $parsed_url['path'] : '';
+    $query = isset($parsed_url['query']) ? $parsed_url['query'] : [];
+    $language = $form_state->getValue('language')[0]['value'];
+    $redirect = \Drupal::service('redirect.repository')->findMatchingRedirect($path, $query, $language);

-    if (!empty($redirects)) {
-      $redirect = array_shift($redirects);
+    if (!empty($redirect)) {
       if ($this->entity->isNew() || $redirect->id() != $this->entity->id()) {
         $form_state->setErrorByName('redirect_source', $this->t('The source path %source is already being redirected. Do you want to <a href="@edit-page">edit the existing redirect</a>?',
           [
diff --git a/src/RedirectRepository.php b/src/RedirectRepository.php
index ff1ccf8b..53ee4981 100644
--- a/src/RedirectRepository.php
+++ b/src/RedirectRepository.php
@@ -6,6 +6,7 @@
 use Drupal\Core\Database\Connection;
 use Drupal\Core\Entity\EntityTypeManagerInterface;
 use Drupal\Core\Language\Language;
+use Drupal\Core\Language\LanguageInterface;
 use Drupal\redirect\Entity\Redirect;
 use Drupal\redirect\Exception\RedirectLoopException;

@@ -69,6 +70,15 @@ public function findMatchingRedirect($source_path, array $query = [], $language
       $hashes[] = Redirect::generateHash($source_path, $query, Language::LANGCODE_NOT_SPECIFIED);
     }

+    // The source path might be an alias, so add the source for the alias if it
+    // is. The alias manager will return the source path as is if it's not an
+    // alias, which will lead to a duplicate it in the hashes array, deal with
+    // that too.
+    $alias_language = ($language == Language::LANGCODE_NOT_SPECIFIED) ? NULL : $language;
+    $alias_source = ltrim(\Drupal::service('path.alias_manager')->getPathByAlias('/' . $source_path, $alias_language), '/');
+    $hashes[] = Redirect::generateHash($alias_source, $query, Language::LANGCODE_NOT_SPECIFIED);
+    $hashes = array_unique($hashes);
+
     // Add a hash without the query string if using passthrough querystrings.
     if (!empty($query) && $this->config->get('passthrough_querystring')) {
       $hashes[] = Redirect::generateHash($source_path, [], $language);
diff --git a/tests/src/Functional/RedirectUITest.php b/tests/src/Functional/RedirectUITest.php
index 34ab60c7..cdfc7a55 100644
--- a/tests/src/Functional/RedirectUITest.php
+++ b/tests/src/Functional/RedirectUITest.php
@@ -91,6 +91,7 @@ public function testAutomaticRedirects() {
     // Test that changing the path back deletes the first redirect, creates
     // a new one and does not result in a loop.
     $this->drupalPostForm('node/' . $node->id() . '/edit', ['path[0][alias]' => '/node_test_alias'], t('Save'));
+    \Drupal::service('path.alias_manager')->cacheClear();
     $redirect = $this->repository->findMatchingRedirect('node_test_alias', [], Language::LANGCODE_NOT_SPECIFIED);
     $this->assertTrue(empty($redirect));

diff --git a/tests/src/Kernel/RedirectAPITest.php b/tests/src/Kernel/RedirectAPITest.php
index 972d0c71..303fffd0 100644
--- a/tests/src/Kernel/RedirectAPITest.php
+++ b/tests/src/Kernel/RedirectAPITest.php
@@ -160,6 +160,18 @@ public function testRedirectEntity() {
     else {
       $this->fail('findMatchingRedirect is case sensitive.');
     }
+
+    // Redirects to a path alias should be findable by the alias's source as the
+    // hash is based on the alias's source.
+    \Drupal::service('path.alias_storage')->save('/node', '/node-alias');
+    $redirect = $this->controller->create();
+    $redirect->setSource('node-alias');
+    $redirect->setRedirect('/some-different-url');
+    $redirect->save();
+    $found = $repository->findMatchingRedirect('/node');
+    $message = 'Failed to find a redirect to a path alias by searching for the path source.';
+    $this->assertInstanceOf(Redirect::class, $found, $message);
+    $this->assertEqual($redirect->getHash(), $found->getHash(), $message);
   }

   /**