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CGST, SGST and IGST Explained with Simple Examples

Confused about which tax applies on your bill? Here is the intra-state vs inter-state rule with real numbers.

8 June 2026 6 min readBy SmartGST Team
CGST, SGST and IGST Explained with Simple Examples

The one rule you need

If the supplier and the place of supply are in the same state, charge CGST + SGST (each half of the rate). If they are in different states or a Union Territory without legislature, charge IGST at the full rate.

Example: Lucknow to Kanpur

A Lucknow trader sells ₹10,000 of goods at 18% to a Kanpur buyer. Both are in Uttar Pradesh, so the invoice shows CGST ₹900 and SGST ₹900. Total ₹11,800.

Example: Lucknow to Mumbai

The same sale to a Mumbai buyer is inter-state. The invoice shows IGST ₹1,800. Total remains ₹11,800 but the tax goes to the Centre and is later apportioned.

Place of supply for services

For most B2B services, the place of supply is the recipient's registered location. For events, transport and immovable property there are specific rules under Section 12 of the IGST Act.

Automate it

SmartGST reads the state code from your business GSTIN and your client's GSTIN and chooses CGST/SGST or IGST automatically, so you never file a wrong split.

Try it on your next invoice

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Keywords: cgst sgst igst difference · intra state inter state gst. This article is general information, not professional tax advice.