GSTIN Structure Decoded: How to Extract PAN and Verify States Offline

The Input Tax Credit (ITC) Risk

Under the current Indian GST regime, claiming Input Tax Credit (ITC) is a major audit concern. If you do business with a supplier who provides a fake, suspended, or structurally malformed GSTIN, your ITC claim will be blocked. Reconciling these discrepancies during annual audits is a massive administrative bottleneck.

Usually, checking a vendor requires logging into the official government portal, typing in the 15-digit code, and solving a captcha. Doing this for 50+ bills a day is slow.

You can perform a first-line-of-defense audit instantly by understanding the structure of the 15-digit GST Identification Number (GSTIN).

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Decoding the 15-Digit GSTIN Format

The GSTIN is not a random number; it is a highly structured, alphanumeric identifier. Let's break down its 5 parts:

[27] [AAAAA0000A] [1] [Z] [5]
 ──   ──────────   ─   ─   ─
 1        2        3   4   5

1. State Code (Digits 1-2): Represents the state of registration as per the Indian Census 2011 code directory. Maharashtra is 27, Delhi is 07, Karnataka is 29, etc.
2. PAN (Digits 3-12): The Permanent Account Number of the business entity. This 10-character PAN allows you to verify the tax identity of the business.
3. Entity Code (Digit 13): Represents the number of registrations the entity has within the same state. Typically 1 for the first registration, 2 for the second, and so on.
4. Default Z (Digit 14): By default, this is the character Z for all registrations.
5. Checksum (Digit 15): A checksum character (can be a digit or a letter) calculated mathematically to detect data entry errors.

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Complete GST State Code Directory

Here are the official State Prefix Codes used as the first two digits of any valid GSTIN:

State Code	State Name	State Code	State Name
01	Jammu & Kashmir	19	West Bengal
02	Himachal Pradesh	20	Jharkhand
03	Punjab	21	Odisha
04	Chandigarh	22	Chhattisgarh
05	Uttarakhand	23	Madhya Pradesh
06	Haryana	24	Gujarat
07	Delhi	27	Maharashtra
08	Rajasthan	29	Karnataka
09	Uttar Pradesh	30	Goa
10	Bihar	32	Kerala
11	Sikkim	33	Tamil Nadu
12	Arunachal Pradesh	34	Puducherry
13	Nagaland	35	Andaman & Nicobar
14	Manipur	36	Telangana
15	Mizoram	37	Andhra Pradesh
16	Tripura	38	Ladakh

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How to Extract a PAN from a GSTIN

Since the 3rd to 12th digits of a GSTIN contain the business PAN, you can extract it instantly. For example, in the GSTIN 27ABCDE1234F1Z5:

• Skip the first 2 digits (27).
• Extract the next 10 characters: ABCDE1234F.
• This is the PAN of the business entity.

By validating this PAN against the Income Tax database, you can confirm whether the vendor is filing their corporate returns, helping you mitigate ITC rejection risk.

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Instant Offline Auditing with GSTCalc

To speed up verification workflows, GSTCalc.online features an Instant GSTIN Profiler on the homepage.

Instead of waiting for slow official API logins:

1. Type the GSTIN into our checker.
2. Our algorithm immediately decodes the state registration name, extracts the PAN, checks character 14 (Z validation), and verifies the structural format.
3. Everything runs locally in your browser sandbox, keeping your vendor queries private.

Bookmark GSTCalc.online to audit vendor stacks in seconds.