GSTR9 tax calculations by Department.

This discussion explains the method the GST Department uses to calculate tax liability from GSTR9 and GSTR9C filings. They primarily compare sales figures from GSTR-1 and GSTR-3B, taking the higher amount. Input Tax Credit (ITC) is then deducted as per GSTR-2B. If the calculated net liability exceeds the amount already paid, a notice may be issued. Matching figures in GSTR-1 and GSTR-3B generally avoids additional liability.