XYZ making late payment of monthly GST and therefore liable to pay Interest. E.g. if he is paying GST today and total GST payable is ₹ 100/- while today he has got balance of unutilized input tax credit of ₹ 80/-, therefore he will be paying ₹ 20/- in cash. As far as interest is concerned, he has to calculate on ₹ 100/- or only on ₹ 20/-?
Interest on full tax liability: interest is calculated on entire GST due even if input tax credit is available. Interest on late GST payment is computed on the entire tax liability; unutilized input tax credit in the credit ledger remains unutilized until it is set off by filing GSTR 3B, and until such set off the base for interest calculation is the gross GST payable. (AI Summary)