diff --git a/src/wp-includes/rest-api/class-wp-rest-server.php b/src/wp-includes/rest-api/class-wp-rest-server.php
index 4f5ae7650d..9d4a5fec05 100644
--- a/src/wp-includes/rest-api/class-wp-rest-server.php
+++ b/src/wp-includes/rest-api/class-wp-rest-server.php
@@ -1012,13 +1012,15 @@ class WP_REST_Server {
 	public function get_index( $request ) {
 		// General site data.
 		$available = array(
-			'name'           => get_option( 'blogname' ),
-			'description'    => get_option( 'blogdescription' ),
-			'url'            => get_option( 'siteurl' ),
-			'home'           => home_url(),
-			'namespaces'     => array_keys( $this->namespaces ),
-			'authentication' => array(),
-			'routes'         => $this->get_data_for_routes( $this->get_routes(), $request['context'] ),
+			'name'            => get_option( 'blogname' ),
+			'description'     => get_option( 'blogdescription' ),
+			'url'             => get_option( 'siteurl' ),
+			'home'            => home_url(),
+			'gmt_offset'      => get_option( 'gmt_offset' ),
+			'timezone_string' => get_option( 'timezone_string' ),
+			'namespaces'      => array_keys( $this->namespaces ),
+			'authentication'  => array(),
+			'routes'          => $this->get_data_for_routes( $this->get_routes(), $request['context'] ),
 		);
 
 		$response = new WP_REST_Response( $available );
diff --git a/tests/phpunit/tests/rest-api/rest-server.php b/tests/phpunit/tests/rest-api/rest-server.php
index cda4a4f4cc..046d2b5f62 100644
--- a/tests/phpunit/tests/rest-api/rest-server.php
+++ b/tests/phpunit/tests/rest-api/rest-server.php
@@ -646,6 +646,8 @@ class Tests_REST_Server extends WP_Test_REST_TestCase {
 		$this->assertArrayHasKey( 'description', $data );
 		$this->assertArrayHasKey( 'url', $data );
 		$this->assertArrayHasKey( 'home', $data );
+		$this->assertArrayHasKey( 'gmt_offset', $data );
+		$this->assertArrayHasKey( 'timezone_string', $data );
 		$this->assertArrayHasKey( 'namespaces', $data );
 		$this->assertArrayHasKey( 'authentication', $data );
 		$this->assertArrayHasKey( 'routes', $data );
diff --git a/tests/qunit/fixtures/wp-api-generated.js b/tests/qunit/fixtures/wp-api-generated.js
index 23a2fb918b..b4c6109baf 100644
--- a/tests/qunit/fixtures/wp-api-generated.js
+++ b/tests/qunit/fixtures/wp-api-generated.js
@@ -10,6 +10,8 @@ mockedApiResponse.Schema = {
     "description": "Just another WordPress site",
     "url": "http://example.org",
     "home": "http://example.org",
+    "gmt_offset": "0",
+    "timezone_string": "",
     "namespaces": [
         "oembed/1.0",
         "wp/v2"