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GSTIN › GSTIN format
GSTIN format: what the 15 characters mean
Every GST registration in India gets a 15-character GSTIN (Goods and Services Tax Identification Number). It is not a random number: each part tells you something, and the last character proves the other fourteen were written correctly.
The five parts of a GSTIN
Take the sample number 03ABCDE1234F1ZA (made up for this page):
| Characters | In the sample | What they mean |
|---|---|---|
| 1–2 | 03 | State code of the registration. 03 is Punjab. See the list of GST state codes. |
| 3–12 | ABCDE1234F | The PAN of the business. For a tax deductor registered under GST (14th character D), this part is the TAN instead. |
| 13 | 1 | Registration number of this PAN in this state: 1 for the first, 2 for the second, and so on; after 9 come the letters A to Z. A business with two registrations in one state (for example two business verticals) has 1 and 2 here. |
| 14 | Z | Z for normal taxpayers. D is used for tax deductors (TDS under GST) and C for tax collectors (e-commerce operators collecting TCS). |
| 15 | A | Check character, worked out from the first 14 (see below). |
The PAN inside tells the type of business
The 4th letter of a PAN shows who holds it, so the 6th character of a GSTIN tells you the same:
- P individual (also a proprietor, who registers under his or her own PAN)
- C company · F firm or LLP · H Hindu undivided family (HUF)
- A association of persons · B body of individuals · T trust
- L local authority · J artificial juridical person · G government
So in 03ABCDE1234F1ZA the 4th letter of the PAN is D, which is not one of these; our checker would warn you. A real proprietor's GSTIN has P there.
How the check character is worked out
Each character gets a value: digits 0–9 are 0–9, letters A–Z are 10–35. Then, for the first 14 characters:
- Multiply the value by 1 for characters in odd places (1st, 3rd, 5th…) and by 2 for characters in even places.
- Split each product into "how many 36s" and "what is left", and add the two. (For example 70 = one 36 and 34 left, so it counts 1 + 34 = 35.)
- Add the results of all 14 characters.
- Divide the total by 36 and take the remainder. 36 minus the remainder is the value of the check character (a remainder of 0 gives 0).
For the sample 03ABCDE1234F1Z the 14 results are 0, 6, 10, 22, 12, 26, 14, 2, 2, 6, 4, 30, 1 and 35. They add up to 170. 170 ÷ 36 leaves 26, and 36 − 26 = 10, which is the letter A. So the full GSTIN is 03ABCDE1234F1ZA.
Common mistakes when writing a GSTIN
- O and 0, I and 1, S and 5, B and 8 mixed up. The PAN part has letters in places 3–7 and 12, digits in 8–11.
- A space or a missing character when copying from a visiting card or a WhatsApp message.
- The GSTIN of another state of the same business. A business registered in Punjab and Haryana has two GSTINs (03… and 06…); bill the one in the state you supply to.