diff -u b/core/includes/config.inc b/core/includes/config.inc
--- b/core/includes/config.inc
+++ b/core/includes/config.inc
@@ -24,7 +24,10 @@
  *   The name of the module or theme to install default configuration for.
  */
 function config_install_default_config($type, $name) {
-  // Get all default configuration owned by this extension.
+  // Get all default configuration owned by this extension. This will return any
+  // configuration that starts with the extension name that exists in any
+  // enabled extension's config directory. This includes the extension that is
+  // being installed.
   $source_storage = new ExtensionInstallStorage();
   $config_to_install = $source_storage->listAll($name . '.');
 
@@ -42,7 +45,7 @@
     $enabled_extensions += array_keys(array_filter(list_themes(), function ($theme) {return $theme->status;}));
 
     $other_module_config = array_filter($other_module_config, function ($config_name) use ($enabled_extensions) {
-      $provider = Unicode::substr($config_name,0, strpos($config_name, '.'));
+      $provider = Unicode::substr($config_name, 0, strpos($config_name, '.'));
       return in_array($provider, $enabled_extensions);
     });
 
diff -u b/core/modules/config/lib/Drupal/config/Tests/ConfigOtherModuleTest.php b/core/modules/config/lib/Drupal/config/Tests/ConfigOtherModuleTest.php
--- b/core/modules/config/lib/Drupal/config/Tests/ConfigOtherModuleTest.php
+++ b/core/modules/config/lib/Drupal/config/Tests/ConfigOtherModuleTest.php
@@ -27,12 +27,18 @@
     );
   }
 
+  /**
+   * Sets up the module handler for enabling and disabling modules.
+   */
   public function setUp() {
     parent::setUp();
     $this->moduleHandler = $this->container->get('module_handler');
   }
 
-  public function testInstallOtherModule() {
+  /**
+   * Tests enabling the provider of the default configuration first.
+   */
+  public function testInstallOtherModuleFirst() {
     $this->moduleHandler->enable(array('config_other_module_config'));
 
     // Check that the config entity doesn't exist before the config_test module
@@ -44,7 +50,7 @@
     // Install the module that provides the entity type. This installs the
     // default configuration.
     $this->moduleHandler->enable(array('config_test'));
-    $this->assertTrue(entity_load('config_test', 'other_module', TRUE),'Default configuration has been installed.');
+    $this->assertTrue(entity_load('config_test', 'other_module', TRUE), 'Default configuration has been installed.');
 
     // Uninstall the module that provides the entity type. This will remove the
     // default configuration.
@@ -80,2 +86,13 @@
 
+  /**
+   * Tests enabling the provider of the config entity type first.
+   */
+  public function testInstallConfigEnityModuleFirst() {
+    $this->moduleHandler->enable(array('config_test'));
+    $this->assertFalse(entity_load('config_test', 'other_module', TRUE), 'Default configuration provided by config_other_module_config does not exist.');
+
+    $this->moduleHandler->enable(array('config_other_module_config'));
+    $this->assertTrue(entity_load('config_test', 'other_module', TRUE), 'Default configuration provided by config_other_module_config has been installed.');
+  }
+
 }