$re = '/(^(1?)(\s?)([\s]?)((\(\d{3}\))|(\d{3}))([\s]?)([\s-]?)(\d{3})([\s-]?)(\d{4})+$)/mi';
$str = '555-555-5555
(555)555-5555
(555) 555-5555
555 555 5555
1 555 555 5555
800-692-7753
6505552368
-1 (757) 622-7382
555)-555-5555
(555-555-5555
1 (555) 555-5555
8oo-six427676;laskdjf';
preg_match_all($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