First Setoff Igst liability against Igst ITC, balance IGST credit to be sett off against CGST liability, and balance with SGST.. in your case.. 80000-12000=68000 IGST Setoff 68000-45000=23000 CGST Setoff 45000-23000=22000 Setoff available to the extent of balance IGST credit and balance SGST of Rs. 22000 payable in cash... Above calculation is specific for your case and that too considering as normal output liability, if any RCM liability is added in above Output tax than the same is not to be Setoff against IGST ITC, RCM liability is to be paid in cash only.....