$re = '/(^\(868\)\ \d{3}\ \d{4})|(^868\d{7})|(^868\-\d{3}\-\d{4})|(^868\ \d{3}\-\d{4})/m';
$str = '8680000000
(868) 000 0000
868-000-0000
868 000-0000
8880000000
767-000-0000
868-0000000
(868)0000000
';
preg_match_all($re, $str, $matches, PREG_SET_ORDER, 0);
// Print the entire match result
var_dump($matches);
Please keep in mind that these code samples are automatically generated and are not guaranteed to work. If you find any syntax errors, feel free to submit a bug report. For a full regex reference for PHP, please visit: http://php.net/manual/en/ref.pcre.php