$re = '/(\d{3}) - (\d{8}) #region code, -, phone number
| #alternative
(\d{4}) - (\d{7,8})#region code, -, phone number/x';
$str = '021-54749110
0531-88881234
0635-8238080';
preg_match_all($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