The import process in GST are as follows: 1) At first, create a Purchase Order. The purchase order always con sists of basic customs duty condition(JCDB) which should be linked to custom vendor and input zero tax code under invoice tab. 2) Now create custom invoice, and in this custom the new field for assessable value will be available and this assessable field will not be editable if the planned delivery cost involved. 3)Now please enter values in amount quantity and assessable value fields and maintain the IGST tac code. This IGST will be calculated on basic custom duty +Assessable value. 4)Now via, t-code MIGO please perform goods as the standard import process. 5)Now at last please perform final invoice with transaction code MIGO.