How to Make a GST Invoice in India

A complete guide to GST-compliant invoicing

An Indian GST invoice must show your 15-digit GSTIN, the recipient's GSTIN for B2B sales, a serial number unique to the financial year, HSN codes for goods or SAC codes for services, the place of supply, and the tax breakup: CGST plus SGST intra-state, IGST inter-state, at the standard 18% rate. Turnover above ₹5 crore also requires registering each invoice on the Invoice Registration Portal for an IRN and QR code.

Invoicing in India requires compliance with local GST regulations and specific formatting standards. Whether you are a freelancer, small business owner, or agency, this guide covers everything you need to create professional, legally compliant invoices in India using INR (₹).

Legal Requirements for India Invoices

✓Display your GSTIN (Goods and Services Tax Identification Number) on all B2B invoices. GSTIN is mandatory for businesses with annual turnover exceeding ₹40 lakh (₹20 lakh for special category states).
✓Include the correct HSN (Harmonized System of Nomenclature) codes for goods or SAC (Services Accounting Code) for services on every invoice to classify the supply properly.
✓Break down GST into CGST and SGST for intra-state supplies, or apply IGST for inter-state supplies. The tax breakup must be clearly shown on the invoice.
✓Generate e-invoices through the GST e-invoice portal (Invoice Registration Portal) if your aggregate turnover exceeds ₹5 crore. E-invoicing is mandatory and generates a unique Invoice Reference Number (IRN).
✓Include a digital signature on e-invoices as mandated by the CBIC. The e-invoice portal signs the invoice JSON with a digital certificate, producing a signed QR code.
✓Determine the place of supply correctly, as it dictates whether CGST+SGST or IGST applies. The place of supply rules differ for goods (location of delivery) and services (location of recipient).
✓Apply the reverse charge mechanism (RCM) where applicable, such as for specified goods and services or purchases from unregistered dealers, and clearly note RCM on the invoice.

Step-by-Step: Create an Invoice for India

Follow these steps to create a compliant India invoice with proper GST handling.

Estimated time: About 10 minutes

1
Set Up Your GSTIN and Business Profile
Enter your 15-digit GSTIN, legal business name, trade name if different, registered address, and state code. Your GSTIN must be valid and active on the GST portal. If you operate in multiple states, set up a profile for each state registration.
2
Verify Client GSTIN
Enter and verify your client's GSTIN using the GST portal's search facility. For B2B invoices, a valid client GSTIN ensures the recipient can claim Input Tax Credit (ITC). For B2C invoices over ₹2.5 lakh, the client's name, address, and state code are mandatory.
3
Add HSN/SAC Codes for Each Item
Assign the correct HSN code (for goods) or SAC code (for services) to every line item. The number of required HSN digits depends on your turnover: 4 digits for turnover up to ₹5 crore, and 6 digits for turnover above ₹5 crore.
4
Select the Correct Tax Type
Determine whether the supply is intra-state (within the same state, attracting CGST + SGST) or inter-state (between different states or export, attracting IGST). This is based on the place of supply rules and directly affects the tax calculation.
5
Generate E-Invoice if Applicable
If your turnover exceeds ₹5 crore, generate the invoice through the Invoice Registration Portal (IRP) to obtain an Invoice Reference Number (IRN) and signed QR code. The IRP validates and registers the invoice on the GST network automatically.
6
Include the QR Code
For B2C invoices by businesses with turnover exceeding ₹500 crore, a dynamic QR code is mandatory. For e-invoices, the QR code is auto-generated by the IRP. The QR code contains key invoice details and allows quick verification.
7
Generate and Download the PDF
Create a PDF invoice that includes all mandatory fields: supplier and recipient details with GSTINs, HSN/SAC codes, tax breakup (CGST/SGST or IGST), place of supply, invoice number, and date. For e-invoices, include the IRN and QR code.
8
File on the GST Portal
Report the invoice in your GSTR-1 return (outward supplies) by the 11th of the following month. E-invoices are auto-populated in GSTR-1. Ensure your invoice data matches the portal records to avoid ITC mismatches for your clients.

Tips for Invoicing in India

Stay updated on e-invoicing threshold changes. The government has progressively lowered the threshold from ₹500 crore to ₹5 crore and may reduce it further. Non-compliance attracts penalties of 100% of the tax due or ₹10,000, whichever is greater.
Use the correct number of HSN code digits based on your turnover slab. Using fewer digits than required can lead to rejection of the invoice on the e-invoice portal and issues during GST audits.
File your GSTR-1 and GSTR-3B on time to ensure your clients can claim their Input Tax Credit without delays. Late filing also attracts a late fee of ₹50 per day (₹20 for nil returns) capped at ₹10,000.
Maintain digital copies of all invoices, debit notes, and credit notes for at least 72 months (6 years) from the due date of the annual return. Digital storage is accepted and recommended by the CBIC.
Regularly reconcile your sales records with GSTR-2A/2B to identify any mismatches in ITC claims. Discrepancies can trigger notices from the GST department and delay ITC availability for your clients.

India Invoicing FAQ

When is GSTIN mandatory on an invoice?

GSTIN is mandatory on all B2B invoices regardless of the amount. For B2C invoices, GSTIN of the supplier is always required, and the recipient's details (name, address, state) become mandatory when the invoice value exceeds ₹2.5 lakh. Businesses with turnover below the registration threshold (₹40 lakh for goods, ₹20 lakh for services) can operate without GSTIN.

What is the difference between CGST, SGST, and IGST?

CGST (Central GST) and SGST (State GST) are levied together on intra-state supplies, each at half the total GST rate. For example, an 18% GST item attracts 9% CGST and 9% SGST. IGST (Integrated GST) is levied at the full rate on inter-state supplies and imports, and is later settled between the central and destination state governments.

How does e-invoicing work in India?

E-invoicing requires you to generate your invoice in a standard JSON format and upload it to the Invoice Registration Portal (IRP). The IRP validates the data, generates a unique Invoice Reference Number (IRN) and a signed QR code, and pushes the data to both the GST portal and the e-way bill portal. The invoice is only considered valid once it has an IRN.

What are the mandatory fields on an Indian GST invoice?

A GST invoice must include: supplier name, address, and GSTIN; recipient name, address, and GSTIN (for B2B); a consecutive serial number unique for each financial year; date of issue; HSN/SAC codes; description of goods or services; quantity and unit; taxable value; GST rate and amount (CGST+SGST or IGST split); place of supply; and total invoice value. Reverse charge transactions must be explicitly marked.

What happens if I issue an invoice with incorrect GST details?

Incorrect GST details can prevent your client from claiming Input Tax Credit, and you may face penalties under Section 122 of the CGST Act. To correct errors, you should issue a credit note (to reduce tax) or debit note (to increase tax) referencing the original invoice. For e-invoices, you cannot amend the original; you must cancel it within 24 hours on the IRP and issue a fresh invoice.