Assam — GST State Code 18

State · every Assam GSTIN begins with 18

Reading a Assam GSTIN

18AAAAA0000A1Z5

The first two digits (18) are the state code, the next ten the business's PAN, the 13th the entity number, and the 15th a checksum. Verify any number instantly with the GSTIN validator.

CGST + SGST or IGST?

Selling within Assam — seller and place of supply both under code 18 — splits the GST equally into CGST and SGST: an 18% supply becomes 9% + 9%. Selling from Assam to any other code (or buying in from one) makes it an interstate supply with a single IGST line at the full rate. Your customer's GSTIN prefix is the quickest way to know which applies.

GST in Assam

Assam carries GST state code 18 — the north-east's largest GST economy and the first state to ratify the GST constitutional amendment. Tea (half of India's output), oil and gas, and Guwahati's role as the region's distribution hub drive its invoicing volumes.

Frequently asked questions

18. Every GSTIN registered in Assam starts with these two digits — for example 18AAAAA0000A1Z5.

If your registration and the place of supply are both in Assam, split the tax into CGST + SGST. If either side is in another state or UT, charge a single IGST at the same total rate.

A state — intra-state supplies split into CGST + SGST as usual.

Related tools & guides

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