diff --git a/core/lib/Drupal/Core/Config/Entity/Query/Condition.php b/core/lib/Drupal/Core/Config/Entity/Query/Condition.php
index bb20fbe..b0a325f 100644
--- a/core/lib/Drupal/Core/Config/Entity/Query/Condition.php
+++ b/core/lib/Drupal/Core/Config/Entity/Query/Condition.php
@@ -7,6 +7,7 @@
 
 namespace Drupal\Core\Config\Entity\Query;
 
+use Drupal\Component\Utility\Unicode;
 use Drupal\Core\Entity\Query\ConditionBase;
 use Drupal\Core\Entity\Query\ConditionInterface;
 use Drupal\Core\Entity\Query\QueryException;
@@ -33,6 +34,15 @@ public function compile($configs) {
         if (!isset($condition['operator'])) {
           $condition['operator'] = is_array($condition['value']) ? 'IN' : '=';
         }
+
+        // Lowercase condition value(s) for case-insensitive matches.
+        if (is_array($condition['value'])) {
+          $condition['value'] = array_map('Drupal\Component\Utility\Unicode::strtolower', $condition['value']);
+        }
+        else {
+          $condition['value'] = Unicode::strtolower($condition['value']);
+        }
+
         $single_conditions[] = $condition;
       }
     }
@@ -150,6 +160,9 @@ protected function matchArray(array $condition, array $data, array $needs_matchi
    */
   protected function match(array $condition, $value) {
     if (isset($value)) {
+      // We always want a case-insensitive match.
+      $value = Unicode::strtolower($value);
+
       switch ($condition['operator']) {
         case '=':
           return $value == $condition['value'];
diff --git a/core/modules/system/lib/Drupal/system/Tests/Entity/ConfigEntityQueryTest.php b/core/modules/system/lib/Drupal/system/Tests/Entity/ConfigEntityQueryTest.php
index 9a84de9..3926f29 100644
--- a/core/modules/system/lib/Drupal/system/Tests/Entity/ConfigEntityQueryTest.php
+++ b/core/modules/system/lib/Drupal/system/Tests/Entity/ConfigEntityQueryTest.php
@@ -110,7 +110,7 @@ protected function setUp() {
 
     $array['level1']['level2'] = 3;
     $entity = entity_create('config_query_test', array(
-      'label' => $this->randomName() . '_test_contains_' . $this->randomName(),
+      'label' => $this->randomName() . '_TEST_contains_' . $this->randomName(),
       'id' => '5',
       'number' => 53,
       'array' => $array,
@@ -462,6 +462,22 @@ protected function testDotted() {
   }
 
   /**
+   * Tests case sensitivity.
+   */
+  public function testCaseSensitivity() {
+    // Filter by label with a known containing case-sensitive word.
+    $this->queryResults = $this->factory->get('config_query_test')
+      ->condition('label', 'TEST', 'CONTAINS')
+      ->execute();
+    $this->assertResults(array('3', '4', '5'));
+
+    $this->queryResults = $this->factory->get('config_query_test')
+      ->condition('label', 'test', 'CONTAINS')
+      ->execute();
+    $this->assertResults(array('3', '4', '5'));
+  }
+
+  /**
    * Asserts the results as expected regardless of order.
    *
    * @param array $expected