How to Amend B2C to B2B has been explained below in step by Step process: 1. Login to GST Portal https://gst.gov.in with your user name and password.
2. Go to Return Dashboard and then select GSTR1 for the month we are filing.
3. Under GSTR-1 you will see a option under Table 10 amended B2C(Others).
Click on that Option.
4. Select Financial Year, Month and State for which Amendment is Required then click on Amend Details.
5. Once you click on Amend details below option will come. Here you have to reduce the amount of the invoice and taxable value which needs to be shown as B2B.
Now We need to reduce 1000 from the Taxable value and 180 from the Tax part. 6. Invoice and Taxable Amount Reduced from Table 10 needs to be added under Table 4 Along with Invoice Amount, Invoice date and GSTN details. Here we need to add mention GSTN, Invoice Number, Invoice Date Total Invoice value i.e 1180 and Taxable Value 1000 and 180 under the Tax part. After Adding all the details of the B2B invoice click on Save. By this way B2C invoices can be amended to B2B invoice. Your total sale value will same by doing this