Wordpress Custom Reply-To Email

wordpress-reply-to.php

// Sets reply-to if it doesn't exist already.
add_filter( 'wp_mail', 'wp_mail_filter_set_reply_to' );

function wp_mail_filter_set_reply_to( $args ) {
	if (!isset($args['headers'])) {
		$args['headers'] = array();
	}
	
	$headers_ser = serialize($args['headers']);
	
	// Does it exist already?
	if (stripos($headers_ser, 'Reply-To:') !== false) {
		return $args;
	}
	
	$site_name = get_option('blogname');
	//$admin_email = get_option('admin_email');
	$support_email = sanitize_email('reply-email@domain.com');
	
	$reply_to_line = "Reply-To: $site_name <$support_email>";

	if (is_array($args['headers'])) {
		$args['headers'][] = 'h:' . $reply_to_line;
		$args['headers'][] = $reply_to_line . "\r\n";
	} else {
		$args['headers'] .= 'h:' . $reply_to_line . "\r\n";
		$args['headers'] .= $reply_to_line . "\r\n";
	}
	
	return $args;
}