19 September 2019
During F.Y. 2018-19, I have deposited CGS+SGST instead of IGST. In GSTR1 also filed One Bills as CGST+SGST instead of IGST. How to rectify it?
19 September 2019
You can pay the correct taxes now and go for the refund for the improper taxes paid. Further, as the invoice is relating to 2018-19, you can amend the same in your subsequent GSTR-1 return.
29 October 2026
The wrongly paid tax can't be adjusted; pay the correct IGST and claim refund of CGST+SGST under Sec 77 within two years from the date of paying IGST (Rule 89(1A)) — no interest is payable on the IGST so paid.