diff --git a/src/Symfony/Component/Mailer/CHANGELOG.md b/src/Symfony/Component/Mailer/CHANGELOG.md
index 7e7e758dac910..d7057a5bc82ba 100644
--- a/src/Symfony/Component/Mailer/CHANGELOG.md
+++ b/src/Symfony/Component/Mailer/CHANGELOG.md
@@ -10,6 +10,7 @@ CHANGELOG
  * Added possibility to register custom transport for dsn by implementing
    `Symfony\Component\Mailer\Transport\TransportFactoryInterface` and tagging with `mailer.transport_factory` tag in DI.
  * Added `Symfony\Component\Mailer\Test\TransportFactoryTestCase` to ease testing custom transport factories.
+ * Added the File transport
 
 4.3.0
 -----
diff --git a/src/Symfony/Component/Mailer/Tests/Transport/FileTransportFactoryTest.php b/src/Symfony/Component/Mailer/Tests/Transport/FileTransportFactoryTest.php
new file mode 100644
index 0000000000000..c933678a8c0af
--- /dev/null
+++ b/src/Symfony/Component/Mailer/Tests/Transport/FileTransportFactoryTest.php
@@ -0,0 +1,59 @@
+<?php
+
+/*
+ * This file is part of the Symfony package.
+ *
+ * (c) Fabien Potencier <fabien@symfony.com>
+ *
+ * For the full copyright and license information, please view the LICENSE
+ * file that was distributed with this source code.
+ */
+
+namespace Symfony\Component\Mailer\Tests\Transport;
+
+use Symfony\Component\Mailer\Tests\TransportFactoryTestCase;
+use Symfony\Component\Mailer\Transport\Dsn;
+use Symfony\Component\Mailer\Transport\FileTransport;
+use Symfony\Component\Mailer\Transport\FileTransportFactory;
+use Symfony\Component\Mailer\Transport\TransportFactoryInterface;
+
+class FileTransportFactoryTest extends TransportFactoryTestCase
+{
+    public function getFactory(): TransportFactoryInterface
+    {
+        return new FileTransportFactory($this->getDispatcher(), $this->getClient(), $this->getLogger());
+    }
+
+    public function supportsProvider(): iterable
+    {
+        yield [
+            new Dsn('smtp', 'null', null, null, null, ['path' => sys_get_temp_dir().'/symfony/emails']),
+            true,
+        ];
+
+        yield [
+            new Dsn('smtp', 'null'),
+            false,
+        ];
+
+        yield [
+            new Dsn('smtp', 'example.com'),
+            false,
+        ];
+    }
+
+    public function createProvider(): iterable
+    {
+        $path = sys_get_temp_dir().'/symfony/emails';
+
+        yield [
+            new Dsn('file', 'null', null, null, null, ['path' => $path]),
+            new FileTransport($path, $this->getDispatcher(), $this->getLogger()),
+        ];
+    }
+
+    public function unsupportedSchemeProvider(): iterable
+    {
+        yield [new Dsn('foo', 'null')];
+    }
+}
diff --git a/src/Symfony/Component/Mailer/Tests/Transport/FileTransportTest.php b/src/Symfony/Component/Mailer/Tests/Transport/FileTransportTest.php
new file mode 100644
index 0000000000000..ba58c6226c0d6
--- /dev/null
+++ b/src/Symfony/Component/Mailer/Tests/Transport/FileTransportTest.php
@@ -0,0 +1,46 @@
+<?php
+
+/*
+ * This file is part of the Symfony package.
+ *
+ * (c) Fabien Potencier <fabien@symfony.com>
+ *
+ * For the full copyright and license information, please view the LICENSE
+ * file that was distributed with this source code.
+ */
+
+namespace Symfony\Component\Mailer\Tests\Transport;
+
+use PHPUnit\Framework\TestCase;
+use Symfony\Component\Filesystem\Filesystem;
+use Symfony\Component\Mailer\SentMessage;
+use Symfony\Component\Mailer\SmtpEnvelope;
+use Symfony\Component\Mailer\Transport\FileTransport;
+use Symfony\Component\Mime\Address;
+use Symfony\Component\Mime\RawMessage;
+
+/**
+ * @group time-sensitive
+ */
+class FileTransportTest extends TestCase
+{
+    public function testSend()
+    {
+        $path = sys_get_temp_dir().'/symfony/emails';
+        (new Filesystem())->remove($path);
+
+        $transport = new FileTransport($path);
+        $message = new RawMessage('');
+        $envelope = new SmtpEnvelope(new Address('fabien@example.com'), [new Address('helene@example.com')]);
+        $transport->send($message, $envelope);
+
+        $file = glob($path.'/*')[0];
+        /** @var SentMessage $sentMessage */
+        $sentMessage = unserialize(file_get_contents($file));
+
+        $this->assertInstanceOf(SentMessage::class, $sentMessage);
+        $this->assertEquals($envelope->getSender(), $sentMessage->getEnvelope()->getSender());
+        $this->assertEquals($envelope->getRecipients(), $sentMessage->getEnvelope()->getRecipients());
+        $this->assertEquals($message, $sentMessage->getMessage());
+    }
+}
diff --git a/src/Symfony/Component/Mailer/Transport/FileTransport.php b/src/Symfony/Component/Mailer/Transport/FileTransport.php
new file mode 100644
index 0000000000000..234ac63e27e8f
--- /dev/null
+++ b/src/Symfony/Component/Mailer/Transport/FileTransport.php
@@ -0,0 +1,46 @@
+<?php
+
+/*
+ * This file is part of the Symfony package.
+ *
+ * (c) Fabien Potencier <fabien@symfony.com>
+ *
+ * For the full copyright and license information, please view the LICENSE
+ * file that was distributed with this source code.
+ */
+
+namespace Symfony\Component\Mailer\Transport;
+
+use Psr\Log\LoggerInterface;
+use Symfony\Component\Mailer\SentMessage;
+use Symfony\Contracts\EventDispatcher\EventDispatcherInterface;
+
+/**
+ * Pretends messages have been sent, but just ignores them.
+ *
+ * @author Hugo Alliaume <@kocal>
+ */
+final class FileTransport extends AbstractTransport
+{
+    private $path;
+
+    public function __construct(string $path, EventDispatcherInterface $dispatcher = null, LoggerInterface $logger = null)
+    {
+        parent::__construct($dispatcher, $logger);
+        $this->path = $path;
+        if (!file_exists($this->path)) {
+            if (!mkdir($this->path, 0777, true)) {
+                throw new \RuntimeException(sprintf('Unable to create path "%s".', $this->path));
+            }
+        }
+    }
+
+    protected function doSend(SentMessage $message): void
+    {
+        $file = $this->path.'/'.uniqid().'.message';
+        $serializedMessage = serialize($message);
+        if (false === file_put_contents($file, $serializedMessage)) {
+            throw new \RuntimeException(sprintf('Unable to write sent message in file "%s".', $file));
+        }
+    }
+}
diff --git a/src/Symfony/Component/Mailer/Transport/FileTransportFactory.php b/src/Symfony/Component/Mailer/Transport/FileTransportFactory.php
new file mode 100644
index 0000000000000..aa0031646e493
--- /dev/null
+++ b/src/Symfony/Component/Mailer/Transport/FileTransportFactory.php
@@ -0,0 +1,34 @@
+<?php
+
+/*
+ * This file is part of the Symfony package.
+ *
+ * (c) Fabien Potencier <fabien@symfony.com>
+ *
+ * For the full copyright and license information, please view the LICENSE
+ * file that was distributed with this source code.
+ */
+
+namespace Symfony\Component\Mailer\Transport;
+
+use Symfony\Component\Mailer\Exception\UnsupportedSchemeException;
+
+/**
+ * @author Hugo Alliaume <@kocal>
+ */
+final class FileTransportFactory extends AbstractTransportFactory
+{
+    public function create(Dsn $dsn): TransportInterface
+    {
+        if ('file' === $dsn->getScheme()) {
+            return new FileTransport($dsn->getOption('path'), $this->dispatcher, $this->logger);
+        }
+
+        throw new UnsupportedSchemeException($dsn);
+    }
+
+    public function supports(Dsn $dsn): bool
+    {
+        return 'null' === $dsn->getHost() && null !== $dsn->getOption('path');
+    }
+}
diff --git a/src/Symfony/Component/Mailer/composer.json b/src/Symfony/Component/Mailer/composer.json
index 5c4ad672a7bc8..eb61c09d8e78d 100644
--- a/src/Symfony/Component/Mailer/composer.json
+++ b/src/Symfony/Component/Mailer/composer.json
@@ -24,6 +24,7 @@
     },
     "require-dev": {
         "symfony/amazon-mailer": "^4.4|^5.0",
+        "symfony/filesystem": "^4.4|^5.0",
         "symfony/google-mailer": "^4.4|^5.0",
         "symfony/http-client-contracts": "^1.1",
         "symfony/mailgun-mailer": "^4.4|^5.0",