The Goods and Service Tax Network (GSTN) has notified the impending changes in GSTR-1 Table-12 on GST Portal. The government has notified that from 1st April onwards, it will become mandatory to report minimum 4 digit or 6 digits of HSN (Harmonized System of Nomenclature) Code in Table-12 of GSTR-1 and in Tax Invoice.
Source Taxguru