E-Invoice

01 When do I need an e-way bill or e-invoice? The value and turnover limits that trigger e-way bills and e-invoicing. 02 E-invoice applicability and exempt businesses Who must generate an IRN, which turnover counts, and who is exempt. 03 How IRN generation works What the IRP checks, what comes back, and what happens to GSTR-1 and the e-way bill. 04 E-invoice document types and supply types INV, CRN and DBN; B2B, SEZ, export and deemed export supply types. 05 QR code and signed QR on e-invoices What is inside the signed QR, how to verify it, and the separate B2C dynamic QR. 06 IRN cancellation, time limit and amendments Cancel within 24 hours; after that, use a credit note. Amend in GSTR-1, not on the IRP. 07 Invoice number rules and duplicate IRN 16 characters, unique per year, allowed symbols, and why "Duplicate IRN" appears. 08 Common IRN and e-invoice API errors What each common IRP validation and API error means and how to fix it. 09 Forgot to generate an e-invoice? Consequences and how to fix it What happens when a B2B invoice goes out without an IRN, and how to correct it before your buyer loses ITC.