A non-compliant GST invoice can deny your buyer their input tax credit — and cost you their business. Getting invoicing right is a trust signal for B2B buyers and a legal requirement for all.
Mandatory Fields on a GST Invoice
- Your business name, address, and GSTIN
- Invoice number (consecutive, unique, reset yearly)
- Invoice date
- Buyer's name, address, and GSTIN (for B2B)
- Place of supply (state)
- HSN/SAC code for each item
- Item description, quantity, and unit
- Taxable value per item
- GST rate (CGST+SGST for intra-state, IGST for inter-state)
- GST amount per item and total
- Total invoice amount in words
LetBuyy Auto-Invoicing
LetBuyy generates fully GST-compliant invoices automatically for every order — with your GSTIN, HSN codes, correct CGST/SGST/IGST split, and sequential invoice numbers. Download, email, or WhatsApp to buyers in one click.
HSN Codes: Getting Them Right
HSN (Harmonized System of Nomenclature) codes classify goods for GST purposes. Using the wrong HSN code means you've applied the wrong tax rate. For apparel: 6101–6117. For footwear: 6401–6405. For electronics: 8501–8548. When in doubt, use the GST portal's HSN search tool.
E-Invoice Mandate
If your annual turnover exceeds ₹5 crore, you must generate invoices through the GST e-invoice portal (IRP) and attach an IRN (Invoice Reference Number) and QR code. LetBuyy integrates with the IRP for merchants above this threshold.