$re = '/^\(?\d{3}\)?[\s.-]?\d{3}[\s.-]?\d{4}$/m';
$str = '1-718-444-1122
718-444-1122
(718)-444-1122
17184441122
7184441122
718.444.1122
1718.444.1122
1-123-456-7890
1 123-456-7890
1 (123) 456-7890
1 123 456 7890
1.123.456.7890
+91 (123) 456-7890
18005551234
1 800 555 1234
+1 800 555-1234
+86 800 555 1234
1-800-555-1234
1 (800) 555-1234
(800)555-1234
(800) 555-1234
(800)5551234
800-555-1234
800.555.1234
18001234567
1 800 123 4567
1-800-123-4567
+18001234567
+1 800 123 4567
+1 (800) 123 4567
1(800)1234567
+1800 1234567
1.8001234567
1.800.123.4567
+1 (800) 123-4567
18001234567
1 800 123 4567
+1 800 123-4567
+86 800 123 4567
1-800-123-4567
1 (800) 123-4567
(800)123-4567
(800) 123-4567
(800)1234567
800-123-4567
800.123.4567
1231231231
123-1231231
123123-1231
123-123 1231
123 123-1231
123-123-1231
(123)123-1231
(123)123 1231
(123) 123-1231
(123) 123 1231
+99 1234567890
+991234567890
(555) 444-6789
555-444-6789
555.444.6789
555 444 6789
18005551234
1 800 555 1234
+1 800 555-1234
+86 800 555 1234
1-800-555-1234
1.800.555.1234
+1.800.555.1234
1 (800) 555-1234
(800)555-1234
(800) 555-1234
(800)5551234
800-555-1234
800.555.1234
(003) 555-1212
(103) 555-1212
(911) 555-1212
18005551234
1 800 555 1234
+86 800-555-1234
1 (800) 555-1234';
preg_match_all($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