diff --git a/src/Symfony/Component/Notifier/Bridge/ClickSend/ClickSendTransport.php b/src/Symfony/Component/Notifier/Bridge/ClickSend/ClickSendTransport.php
index 0e5bd147d3f61..f60e4e23ee3f9 100644
--- a/src/Symfony/Component/Notifier/Bridge/ClickSend/ClickSendTransport.php
+++ b/src/Symfony/Component/Notifier/Bridge/ClickSend/ClickSendTransport.php
@@ -87,7 +87,7 @@ protected function doSend(MessageInterface $message): SentMessage
 
         $response = $this->client->request('POST', $endpoint, [
             'auth_basic' => [$this->apiUsername, $this->apiKey],
-            'json' => array_filter($options),
+            'json' => ['messages' => [array_filter($options)]],
         ]);
 
         try {
diff --git a/src/Symfony/Component/Notifier/Bridge/ClickSend/Tests/ClickSendTransportTest.php b/src/Symfony/Component/Notifier/Bridge/ClickSend/Tests/ClickSendTransportTest.php
index 166bb10d8a8dc..ba7923a7fa231 100644
--- a/src/Symfony/Component/Notifier/Bridge/ClickSend/Tests/ClickSendTransportTest.php
+++ b/src/Symfony/Component/Notifier/Bridge/ClickSend/Tests/ClickSendTransportTest.php
@@ -63,10 +63,14 @@ public function testNoInvalidArgumentExceptionIsThrownIfFromIsValid(string $from
         $response = $this->createMock(ResponseInterface::class);
         $response->expects(self::exactly(2))->method('getStatusCode')->willReturn(200);
         $response->expects(self::once())->method('getContent')->willReturn('');
-        $client = new MockHttpClient(function (string $method, string $url) use ($response): ResponseInterface {
+        $client = new MockHttpClient(function (string $method, string $url, array $options) use ($response): ResponseInterface {
             self::assertSame('POST', $method);
             self::assertSame('https://rest.clicksend.com/v3/sms/send', $url);
 
+            $body = json_decode($options['body'], true);
+            self::assertIsArray($body);
+            self::assertArrayHasKey('messages', $body);
+
             return $response;
         });
         $transport = $this->createTransport($client, $from);