Answer

1. F

   Facts

   GSTR-1A lets you add missed invoices or amend details reported in GSTR-1 for the same tax period. It is available after GSTR-1 is filed and before GSTR-3B for that period is filed. Changes flow to GSTR-3B and to the buyer's records.

2. P

   Provisions and law

   • Sec 37, CGST Act 2017Details of outward supplies to be furnished in GSTR-1
   • Rule 59, CGST Rules 2017Form and due date of GSTR-1; monthly filers by the 11th of the next month
3. A

   Analysis

   Missed B2B invoices hurt your buyer, who cannot take credit until your invoice appears in his GSTR-2B. If you add them through GSTR-1A before GSTR-3B, the tax goes into this month's return and no interest arises. If you miss the window, report them in the next month's GSTR-1, pay tax with interest for the delay, and tell the buyer the credit will appear one month later.

4. C

   Conclusion

   1. 1List invoices missing from the filed GSTR-1
   2. 2Open GSTR-1A from the Returns Dashboard for the same period
   3. 3Add or amend the invoices and file GSTR-1A
   4. 4Then file GSTR-3B, which will pick up the updated liability
   5. 5Tell your buyer which period the invoices will reflect in

General guidance from TaxSavvy’s library of money processes. Laws change; your Savvy confirms the answer on your exact case before anything is filed.