Returns filing obligations require electronic monthly or periodic returns with prescribed deadlines and tax payment by return due date. Registered taxable persons must electronically furnish returns of supplies, input tax credit and tax payable/paid according to prescribed periodicity-monthly for regular taxpayers, monthly for TDS deductors and Input Service Distributors, quarterly for persons under section 9, and monthly or within a short post registration period for non residents-with tax payable payable by the return due date. The Commissioner may extend time limits for classes of taxpayers. Nil period returns are required. Post filing omissions or incorrect particulars may be rectified in the period of discovery with applicable interest, subject to a cutoff after the September/second quarter due date or filing of the annual return.