diff --git a/src/wp-includes/class-http.php b/src/wp-includes/class-http.php
index 8917b90c1d..2a458eb705 100644
--- a/src/wp-includes/class-http.php
+++ b/src/wp-includes/class-http.php
@@ -449,7 +449,7 @@ class WP_Http {
 
 		foreach ( $cookies as $name => $value ) {
 			if ( $value instanceof WP_Http_Cookie ) {
-				$cookie_jar[ $value->name ] = new Requests_Cookie( $value->name, $value->value, $value->get_attributes() );
+				$cookie_jar[ $value->name ] = new Requests_Cookie( $value->name, $value->value, $value->get_attributes(), array( 'host-only' => $value->host_only ) );
 			} elseif ( is_scalar( $value ) ) {
 				$cookie_jar[ $name ] = new Requests_Cookie( $name, $value );
 			}
diff --git a/src/wp-includes/class-wp-http-cookie.php b/src/wp-includes/class-wp-http-cookie.php
index 568fe4848a..c265540323 100644
--- a/src/wp-includes/class-wp-http-cookie.php
+++ b/src/wp-includes/class-wp-http-cookie.php
@@ -60,6 +60,14 @@ class WP_Http_Cookie {
 	 */
 	public $domain;
 
+	/**
+	 * host-only flag.
+	 *
+	 * @since 5.2.0
+	 * @var bool
+	 */
+	public $host_only;
+
 	/**
 	 * Sets up this cookie object.
 	 *
@@ -67,16 +75,18 @@ class WP_Http_Cookie {
 	 * or a header string detailing it.
 	 *
 	 * @since 2.8.0
+	 * @since 5.2.0 Added `host_only` to the `$data` parameter.
 	 *
 	 * @param string|array $data {
 	 *     Raw cookie data as header string or data array.
 	 *
-	 *     @type string     $name    Cookie name.
-	 *     @type mixed      $value   Value. Should NOT already be urlencoded.
-	 *     @type string|int $expires Optional. Unix timestamp or formatted date. Default null.
-	 *     @type string     $path    Optional. Path. Default '/'.
-	 *     @type string     $domain  Optional. Domain. Default host of parsed $requested_url.
-	 *     @type int        $port    Optional. Port. Default null.
+	 *     @type string     $name      Cookie name.
+	 *     @type mixed      $value     Value. Should NOT already be urlencoded.
+	 *     @type string|int $expires   Optional. Unix timestamp or formatted date. Default null.
+	 *     @type string     $path      Optional. Path. Default '/'.
+	 *     @type string     $domain    Optional. Domain. Default host of parsed $requested_url.
+	 *     @type int        $port      Optional. Port. Default null.
+	 *     @type bool       $host_only Optional. host-only storage flag. Default true.
 	 * }
 	 * @param string       $requested_url The URL which the cookie was set on, used for default $domain
 	 *                                    and $port values.
@@ -128,7 +138,7 @@ class WP_Http_Cookie {
 			}
 
 			// Set properties based directly on parameters.
-			foreach ( array( 'name', 'value', 'path', 'domain', 'port' ) as $field ) {
+			foreach ( array( 'name', 'value', 'path', 'domain', 'port', 'host_only' ) as $field ) {
 				if ( isset( $data[ $field ] ) ) {
 					$this->$field = $data[ $field ];
 				}
diff --git a/src/wp-includes/class-wp-http-requests-response.php b/src/wp-includes/class-wp-http-requests-response.php
index df0957f6ff..b6c5f24a96 100644
--- a/src/wp-includes/class-wp-http-requests-response.php
+++ b/src/wp-includes/class-wp-http-requests-response.php
@@ -164,11 +164,12 @@ class WP_HTTP_Requests_Response extends WP_HTTP_Response {
 		foreach ( $this->response->cookies as $cookie ) {
 			$cookies[] = new WP_Http_Cookie(
 				array(
-					'name'    => $cookie->name,
-					'value'   => urldecode( $cookie->value ),
-					'expires' => isset( $cookie->attributes['expires'] ) ? $cookie->attributes['expires'] : null,
-					'path'    => isset( $cookie->attributes['path'] ) ? $cookie->attributes['path'] : null,
-					'domain'  => isset( $cookie->attributes['domain'] ) ? $cookie->attributes['domain'] : null,
+					'name'      => $cookie->name,
+					'value'     => urldecode( $cookie->value ),
+					'expires'   => isset( $cookie->attributes['expires'] ) ? $cookie->attributes['expires'] : null,
+					'path'      => isset( $cookie->attributes['path'] ) ? $cookie->attributes['path'] : null,
+					'domain'    => isset( $cookie->attributes['domain'] ) ? $cookie->attributes['domain'] : null,
+					'host_only' => isset( $cookie->flags['host-only'] ) ? $cookie->flags['host-only'] : null,
 				)
 			);
 		}
diff --git a/tests/phpunit/tests/http/functions.php b/tests/phpunit/tests/http/functions.php
index bfa4cd3e2a..3b15c6856e 100644
--- a/tests/phpunit/tests/http/functions.php
+++ b/tests/phpunit/tests/http/functions.php
@@ -199,4 +199,29 @@ class Tests_HTTP_Functions extends WP_UnitTestCase {
 		$this->assertSame( 'test', $cookie->name );
 		$this->assertSame( 'foo', $cookie->value );
 	}
+
+	/**
+	 * @ticket 43231
+	 */
+	function test_get_cookie_host_only() {
+		// emulate WP_Http::request() internals
+		$requests_response = new Requests_Response();
+
+		$requests_response->cookies['test'] = Requests_Cookie::parse( 'test=foo; domain=.wordpress.org' );
+
+		$requests_response->cookies['test']->flags['host-only'] = false; // https://github.com/rmccue/Requests/issues/306
+
+		$http_response = new WP_HTTP_Requests_Response( $requests_response );
+
+		$response = $http_response->to_array();
+
+		// check the host_only flag in the resulting WP_Http_Cookie
+		$cookie = wp_remote_retrieve_cookie( $response, 'test' );
+		$this->assertEquals( $cookie->domain, 'wordpress.org' );
+		$this->assertFalse( $cookie->host_only, 'host-only flag not set' );
+
+		// regurgitate (Requests_Cookie -> WP_Http_Cookie -> Requests_Cookie)
+		$cookies = WP_Http::normalize_cookies( wp_remote_retrieve_cookies( $response ) );
+		$this->assertFalse( $cookies['test']->flags['host-only'], 'host-only flag data lost' );
+	}
 }