If  there is a requirement where you want to create multiple shipping categories in Oscommerce that a user can select like No Shipping :  $0.00 Flat Rate Manhattan: $25.00 Flat Rate Overnight Manhattan: $30.00 Then just follow the steps given below: Create copy of “flat.php” Ex: flat2.php,flat3.php in catalog\includes\modules\shipping and catalog\includes\languages\english\modules\shipping. Open catalog\includes\languages\english\modules\shipping\flat2.php and replace lines with the following….