GST invoice requirements in India

A GST invoice in India must show your GSTIN, the customer's details, an itemised list of what you supplied, and the GST shown separately with its rate — currently 5%, 18%, 40%, with 18% as the usual rate for most services.

The India rule that catches people out

India splits the rate depending on where the customer is. A sale inside your own state is charged as CGST + SGST — half the rate each — and a sale to another state is IGST at the full rate. The total the customer pays is identical; the split matters for your return. Your invoice has to show the place of supply so the split can be checked.

What India adds to the document

Beyond the universal fields: your GSTIN (formatted like 07AAAAA0000A1Z5), and the GST rate and amount shown separately from the net on each line.

Rates

5%, 18%, 40%. Most service work sits at 18%. The slabs were simplified with effect from 22 September 2025: the four-tier structure became a two-rate one — a standard rate of 18% and a merit rate of 5% — with a new special de-merit rate of 40% for a short list of goods and services. Most 12% items moved to 5% and most 28% items to 18%. (Source: Ministry of Finance, recommendations of the 56th GST Council, 3 September 2025; the changes took effect on 22 September 2025 per the Council's own FAQs. Checked 20 September 2026.)

Rates change. Checked to mid-2026 and a starting point, not tax advice. The current source is Central Board of Indirect Taxes and Customs — and if you are near a registration threshold, twenty minutes with an accountant beats a search engine.

When you have to register for GST in India

₹40 lakh of turnover for goods and ₹20 lakh for services in most states, halved in the special-category states. Once you cross, registration is required within thirty days — and the liability starts from the date you crossed, not the date you registered.

Most systems test this on a rolling twelve months rather than your financial year — which is where the expensive mistakes happen.

Which GST rate applies to what

5% covers most essentials and a wide band of services moved down in the 2025 simplification; 18% is the workhorse rate for professional and trade services; 40% is the special de-merit rate for a short list of luxury and sin goods. Nil-rated is not the same as exempt, and the difference decides whether you can claim input credit. Separately from this structure, precious metals and stones carry their own special rates, so if you invoice gold, silver or diamonds do not assume 5% or 18% — look your goods up on the CBIC rate finder.

How often you file in India

GSTR-1 and GSTR-3B monthly, or quarterly under the QRMP scheme if turnover is below ₹5 crore, plus an annual GSTR-9. E-invoicing through the Invoice Registration Portal — which returns the IRN and QR code that make the invoice valid — applies where aggregate turnover crossed ₹5 crore in any financial year since 2017-18, a threshold in force from 1 August 2023. The limit has been lowered repeatedly since 2020, so re-check it rather than assuming you are still outside it.

The place of supply field

Indian invoices carry a place-of-supply code because it decides the CGST/SGST versus IGST split. Get it wrong and the tax lands in the wrong government's account, which is a correction exercise rather than a fine — but it is your correction exercise. For services, the default is the recipient's location where they are registered, and their address on record where they are not.

E-invoicing and the IRN

Businesses above the e-invoicing turnover threshold must report B2B invoices to the Invoice Registration Portal and print the resulting IRN and QR code on the document. The threshold is ₹5 crore of aggregate turnover in any financial year from 2017-18 onwards, and it has applied since 1 August 2023 — the test looks back over every year since GST began, not just last year, so a business that has since shrunk stays inside it. Below the threshold this does not apply, but the limit has been lowered repeatedly since 2020 and is worth re-checking annually.

Sources, read 20 September 2026: the registration thresholds are section 22 of the CGST Act 2017 and its provisos; the retention period is section 36 (seventy-two months from the due date of the annual return); the e-invoicing threshold and the "any preceding financial year since 2017-18" test are stated by GSTN's own e-invoice overview on gst.gov.in. Rates change — check yours on the CBIC rate finder before you invoice.

GST on a discounted invoice

Bill ₹4,100 with a 5% discount shown on the document and the GST is ₹701.1, not ₹738 — the discounted value is what gets taxed. Discounts, deposits and advance payments covers the cases where that stops being obvious.

Invoicing a customer outside India

Export of services is zero-rated, either under a Letter of Undertaking without paying IGST or by paying IGST and claiming a refund. The conditions are strict: payment must be received in convertible foreign exchange and the recipient must be outside India.

Charging tax to a client in another country sets out the general shape; the first time it comes up it is worth an hour with an accountant.

Record keeping in India

Six years from the due date of the annual return — in practice, keep the invoice itself for at least seven. Retention rules mean the document, not a row in a ledger.

Set your country once in EstimateBill and the tax is labelled correctly on every invoice after that — GST and GSTIN in India, VAT in the UK, Sales Tax and EIN in the US, across 58 countries.