Guide

CGST, SGST or IGST: which one to charge

Charge CGST and SGST (half the GST rate each) when the place of supply is in your own state, and IGST (the full rate) when it's in another state. For goods the place of supply is usually where the goods are delivered; for a registered buyer that's normally the state in their GSTIN.

Updated 29 October 2026

The rule in one line

Same state → CGST + SGST (or UTGST in a union territory without a legislature). Different state → IGST. The total tax is the same; only who collects it changes.

Examples (seller in Tamil Nadu, 18% GST on ₹10,000)

Buyer in Chennai: CGST 9% ₹900 + SGST 9% ₹900 = ₹1,800.
Buyer in Bengaluru: IGST 18% ₹1,800.
Walk-in customer at your Chennai counter: CGST + SGST, because the goods are handed over in Tamil Nadu.

How HextaBook decides

HextaBook takes the place of supply from the buyer's GSTIN, else their address's state, and lets you change it on the bill. It charges CGST + SGST or IGST accordingly and reports the sale in the right section of GSTR-1.

Frequently asked questions

What happens if I charge the wrong tax?

If you charged IGST instead of CGST + SGST (or the other way round), you generally have to pay the correct tax and claim a refund of the wrong one, so it's worth getting the place of supply right on the bill.

Do I charge GST to a customer outside India?

An export is usually zero-rated: made under a letter of undertaking (LUT) without IGST, or with IGST paid and refunded. Check with your CA for your case.