GST helpdesk is in receipt of some tickets at helpdesk wherein it was reported that certain 6-digit HSN codes are not available in HSN Master/ not accepted on e-invoice/e-Way bill portals. Background: Notification No. 12/2017-Central Tax dated June 28, 2017, as amended vide Notification No. 78/2020 – Central Tax, dated October 15, 2020, mandates taxpayers to declare specified digits, as follows, of Harmonised System of Nomenclature (HSN) / Service Accounting Code (SAC) Code on raising of tax invoices, w.e.f. April 1, 2021.