$re = '/^(?!(?:1-)?(?:\$|#|(?:\((8(?:00|55|66|77|88))\)|(?1))))\(?[\s.-]*([0-9]{3})?[\s.-]*\)?[\s.-]*[0-9]{3}[\s.-]*[0-9]{4}$/m';
$str = '1-800-450-7006
1 (800) 450-7006
1(800) 450-7006
(800) 450-7006
800 450-7006';
preg_match_all($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