$re = '/^(?<Beleg>[A-Z,0-9]{5,6}).(?<Kontierung>[0-9]{3,5}.[0-9]{3}.[0-9]{2}-[0-9]{2}).(?<Datum>[0-9]{2}.[0-1]{1}[0-9]{1}.[0-9]{2}).(?<VS>[0-9]{3}).(?<US>[0-9]{3})?.(?<UmsatzSoSpace>.?.?.?.?.?.?.?.?.?.?.?.?.?.?.?.?.?)(?<UmsatzSo>[0-9]{0,1}?[0-9]{0,1}?.?[0-9]{0,3}?.?[0-9]{0,3}?.?[0-9]{0,3}?.?[0-9]{0,1}?[0-9]{0,1}?[0-9]{1}?,[0-9]{2}).(?<UmsatzHaSpace>.?.?.?.?.?.?.?.?.?.?.?.?.?.?.?.?)(?<UmsatzHa>[0-9]{0,1}?.?[0-9]{0,3}?.?[0-9]{0,3}?.?[0-9]{0,3}?.?[0-9]{0,1}?[0-9]{0,1}?[0-9]{1}?,[0-9]{2}).(?<GK>[0-9]{2}).(?<Buchungstext>[(\w)(\W)(\s)]{53}).(?<MwSt>[0-9]{0,4}).(?<E_Nr>[0-9]{5})/';
$str = '';
preg_match($re, $str, $matches, PREG_OFFSET_CAPTURE, 0);
// Print the entire match result
var_dump($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