diff -u b/core/modules/migrate/src/MigrateExecutable.php b/core/modules/migrate/src/MigrateExecutable.php
--- b/core/modules/migrate/src/MigrateExecutable.php
+++ b/core/modules/migrate/src/MigrateExecutable.php
@@ -386,7 +386,7 @@
           $multiple = $plugin->multiple();
         }
       }
-      // No plugins or no value means do not set.
+      // Ensure all values, including nulls, are migrated.
       if ($plugins) {
         if (isset($value)) {
           $row->setDestinationProperty($destination, $value);
diff -u b/core/modules/migrate/tests/src/Kernel/MigrateEntityContentBaseTest.php b/core/modules/migrate/tests/src/Kernel/MigrateEntityContentBaseTest.php
--- b/core/modules/migrate/tests/src/Kernel/MigrateEntityContentBaseTest.php
+++ b/core/modules/migrate/tests/src/Kernel/MigrateEntityContentBaseTest.php
@@ -4,6 +4,7 @@
 
 use Drupal\KernelTests\KernelTestBase;
 use Drupal\language\Entity\ConfigurableLanguage;
+use Drupal\migrate\MigrateMessage;
 use Drupal\migrate\MigrateExecutable;
 use Drupal\migrate\Plugin\migrate\destination\EntityContentBase;
 use Drupal\migrate\Plugin\MigrateIdMapInterface;