“Advanced Inclusive Tax Table Rates” system works well in the systems where Tax is involved with the products and we want to leverage shipping charges based on Table Rates method of Magento.

This extension works to rectify the default Magento’s functionality where products which are exclusive of tax need to have the shipping charges levied on them. In Magento’s default functionality this scenario will be handled incorrectly as the shipping charge will be levied on the subtotal exclusive of tax. This scenario can lead to a disadvantage when you want to provide free shipping on orders having a certain subtotal. Since default, Magento does not consider the tax which actually should be considered while calculating shipping charges the orders which should be eligible for free shipping also get shipping charges applied to them.

When we are talking about the scenario where the application of tax and leveraging of shipping charges are involved together in a system, a very complex scenario comes into picture. Magento does not handle efficiently the scenario where tax is involved. If shipping method is Table Rates of Magento and the system is exclusive of tax, then Magento’s default Table rates are working fine but when you introduce tax in your system then table rates are still calculated based on subtotal i.e, exclusive of tax. So to rescue user from these default Magento’s issue, with shipping charges calculation using table rates based on subtotal inclusive of tax, Advanced Inclusive Tax Table Rates can be used. This extension works fine with or without Magento’s tax system.