diff --git a/src/Elasticsearch/Client.php b/src/Elasticsearch/Client.php
index a6b7a9b42..ec4abe36c 100644
--- a/src/Elasticsearch/Client.php
+++ b/src/Elasticsearch/Client.php
@@ -34,6 +34,8 @@
  */
 class Client
 {
+    const VERSION = '7.0.0';
+
     /**
      * @var Transport
      */
diff --git a/src/Elasticsearch/Connections/Connection.php b/src/Elasticsearch/Connections/Connection.php
index 3a0151487..0a1a63168 100644
--- a/src/Elasticsearch/Connections/Connection.php
+++ b/src/Elasticsearch/Connections/Connection.php
@@ -4,6 +4,7 @@
 
 namespace Elasticsearch\Connections;
 
+use Elasticsearch\Client;
 use Elasticsearch\Common\Exceptions\AlreadyExpiredException;
 use Elasticsearch\Common\Exceptions\BadRequest400Exception;
 use Elasticsearch\Common\Exceptions\Conflict409Exception;
@@ -133,6 +134,15 @@ public function __construct(
             unset($connectionParams['client']['headers']);
         }
 
+        // Add the User-Agent using the format: <client-repo-name>/<client-version> (metadata-values)
+        $this->headers['User-Agent'] = [sprintf(
+            "elasticsearch-php/%s (%s %s; PHP %s)",
+            Client::VERSION,
+            php_uname("s"),
+            php_uname("r"),
+            phpversion()
+        )];
+
         $host = $hostDetails['host'].':'.$hostDetails['port'];
         $path = null;
         if (isset($hostDetails['path']) === true) {
@@ -317,6 +327,11 @@ function (&$value, &$key) {
         return $uri ?? '';
     }
 
+    public function getHeaders(): array
+    {
+        return $this->headers;
+    }
+
     /**
      * Log a successful request
      *
diff --git a/tests/Elasticsearch/Tests/Connections/ConnectionTest.php b/tests/Elasticsearch/Tests/Connections/ConnectionTest.php
new file mode 100644
index 000000000..a9eac8a68
--- /dev/null
+++ b/tests/Elasticsearch/Tests/Connections/ConnectionTest.php
@@ -0,0 +1,89 @@
+<?php
+
+declare(strict_types = 1);
+
+namespace Elasticsearch\Tests\Connections;
+
+use Elasticsearch\Client;
+use Elasticsearch\ClientBuilder;
+use Elasticsearch\Connections\Connection;
+use Elasticsearch\Serializers\SerializerInterface;
+use Psr\Log\LoggerInterface;
+
+class ConnectionTest extends \PHPUnit\Framework\TestCase
+{
+    private $logger;
+    private $trace;
+    private $serializer;
+
+    protected function setUp()
+    {
+        $this->logger = $this->createMock(LoggerInterface::class);
+        $this->trace = $this->createMock(LoggerInterface::class);
+        $this->serializer = $this->createMock(SerializerInterface::class);
+    }
+
+    public function testConstructor()
+    {
+        $params = [];
+        $host = [
+            'host' => 'localhost'
+        ];
+
+        $connection = new Connection(
+            function () {
+            },
+            $host,
+            $params,
+            $this->serializer,
+            $this->logger,
+            $this->trace
+        );
+
+        $this->assertInstanceOf(Connection::class, $connection);
+    }
+
+    public function testGetHeadersContainUserAgent()
+    {
+        $params = [];
+        $host = [
+            'host' => 'localhost'
+        ];
+
+        $connection = new Connection(
+            function () {
+            },
+            $host,
+            $params,
+            $this->serializer,
+            $this->logger,
+            $this->trace
+        );
+
+        $headers =  $connection->getHeaders();
+
+        $this->assertArrayHasKey('User-Agent', $headers);
+        $this->assertContains('elasticsearch-php/'. Client::VERSION, $headers['User-Agent'][0]);
+    }
+
+    public function testUserAgentHeaderIsSent()
+    {
+        $params = [];
+        $host = [
+            'host' => 'localhost'
+        ];
+
+        $connection = new Connection(
+            ClientBuilder::defaultHandler(),
+            $host,
+            $params,
+            $this->serializer,
+            $this->logger,
+            $this->trace
+        );
+        $result = $connection->performRequest('GET', '/');
+        $request = $connection->getLastRequestInfo()['request'];
+        $this->assertArrayHasKey('User-Agent', $request['headers']);
+        $this->assertContains('elasticsearch-php/'. Client::VERSION, $request['headers']['User-Agent'][0]);
+    }
+}