GSTIN stands for Goods and Services Tax Identification Number. It is a unique 15-digit alphanumeric code assigned to every registered GST taxpayer in India. The number contains the state code, PAN of the business, entity number, and a check digit for verification.

How many digits are in a GSTIN?

A GSTIN has exactly 15 characters. The first 2 are the state code, the next 10 are the PAN of the business or individual, the 13th character is the entity number (1-9 or A-Z), the 14th is always Z (reserved for future use), and the 15th is a check digit calculated using a specific algorithm.

How do I verify if a GSTIN is valid?

You can verify a GSTIN in two ways. First, check the format: it should be 15 characters matching the pattern of state code + PAN + entity number + Z + check digit. Second, verify it on the official GST portal at gst.gov.in under Search Taxpayer to confirm the registration status, business name, and filing history.

What does each part of a GSTIN represent?

The GSTIN structure is: Characters 1-2 = State/UT code (e.g., 27 for Maharashtra, 07 for Delhi). Characters 3-12 = PAN of the registered person. Character 13 = Entity number for multiple registrations in the same state. Character 14 = Z (default, reserved). Character 15 = Check digit for error detection.

Can a business have multiple GSTINs?

Yes. A business must obtain a separate GSTIN for each state where it operates. Additionally, within the same state, a business can have multiple GSTINs if it has different verticals or branches. The 13th character in the GSTIN (entity number) differentiates between multiple registrations under the same PAN in the same state.

What is the difference between GSTIN and GST Number?

GSTIN and GST Number refer to the same thing. GSTIN is the official term used by the government, while GST Number is the commonly used informal term. Both refer to the 15-digit unique identification number assigned to GST-registered taxpayers.

Why is GSTIN verification important for restaurants?

Restaurants deal with multiple vendors for raw materials, equipment, and services. Verifying a vendor's GSTIN before making payments ensures that you can claim Input Tax Credit (ITC) on eligible purchases. If a vendor's GSTIN is fake or cancelled, your ITC claim will be rejected during GSTR-2B reconciliation.

What happens if I use a wrong GSTIN on an invoice?

Using an incorrect GSTIN on an invoice creates several problems. The buyer cannot claim ITC because the invoice will not match in GSTR-2B. The seller's GSTR-1 will show a mismatch. Both parties may receive notices from the GST department. The invoice may need to be cancelled and reissued with the correct GSTIN using a credit note.

How can I find my own GSTIN?

Your GSTIN is printed on your GST Registration Certificate issued by the government. You can also find it by logging into the GST portal at gst.gov.in with your credentials. If you have your PAN and state code, your GSTIN starts with the state code followed by your PAN, then the entity number, Z, and check digit.

Is GSTIN verification mandatory before issuing invoices?

While not legally mandatory for every transaction, GSTIN verification is a best practice that protects your business. For B2B transactions above Rs 2.5 lakh, the buyer's GSTIN must appear on the invoice for ITC eligibility. Verifying the GSTIN ensures the number is active and belongs to the correct party, preventing future compliance issues.

GSTIN Verification Tool | Validate GST Number Format Online

What is a GSTIN?

GSTIN stands for Goods and Services Tax Identification Number. It is a unique 15-digit alphanumeric code assigned to every registered taxpayer under India's GST system. The number was introduced when GST replaced multiple indirect taxes on July 1, 2017, and serves as the primary identification for all GST-related transactions.

Every business that crosses the GST registration threshold (Rs 40 lakh for goods, Rs 20 lakh for services in most states) must obtain a GSTIN. The number is state-specific, meaning a business operating in multiple states needs a separate GSTIN for each state. It appears on every GST invoice, return filing, and compliance document.

GSTIN is a 15-character alphanumeric code that includes the state code, PAN, entity number, and a check digit
Every GST-registered business, including restaurants, must quote their GSTIN on invoices, delivery challans, and credit notes
The GSTIN is issued by the central government through the GST Portal after registration approval

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How is a GSTIN Structured?

The 15-digit GSTIN follows a fixed format where each segment carries specific information about the registered taxpayer. Understanding this structure helps you spot errors in a GSTIN before using it on an invoice or purchase order.

SS PPPPPPPPPP E Z C

SS (Characters 1-2): State or Union Territory code. For example, 27 = Maharashtra, 07 = Delhi, 29 = Karnataka, 24 = Gujarat

PPPPPPPPPP (Characters 3-12): PAN (Permanent Account Number) of the registered entity. This is the same 10-character PAN issued by the Income Tax Department

E (Character 13): Entity number (1-9 or A-Z). Differentiates multiple registrations under the same PAN in the same state

Z (Character 14): Default character, currently always "Z". Reserved for future use by the government

C (Character 15): Check digit generated using a specific algorithm. Used to detect data entry errors

The PAN embedded in the GSTIN also reveals the type of entity. The fourth character of PAN indicates whether the registration belongs to a company (C), firm/LLP (F), individual (P), Hindu Undivided Family (H), trust (T), or association of persons (A). This is useful when verifying vendor registrations for Input Tax Credit claims.

GSTIN Verification Example

Let's verify a sample GSTIN to understand how the validation works. Consider the GSTIN 27AAPFU0939F1ZV, which belongs to a business registered in Maharashtra.

State Code (27): Maharashtra. Valid state code confirmed

PAN (AAPFU0939F): Valid PAN format. The "F" in the 4th position indicates this is a Firm or LLP

Entity Number (1): This is the first (or only) GST registration under this PAN in Maharashtra

Default Character (Z): Present and correct

Check Digit (V): Verified against the GSTIN check digit algorithm. The number is structurally valid

Format validation confirms the GSTIN follows the correct pattern. For complete verification of registration status (Active, Cancelled, or Suspended), you should also check the official GST Portal search. This tool validates the structure, which catches most data entry errors and fake GSTINs before they reach your invoice.

Why is GSTIN Verification Important?

Verifying a supplier's or customer's GSTIN before issuing invoices protects your business from compliance risks and financial losses. Here is why every business should make GSTIN verification a standard practice:

Protect your ITC claims: If a vendor's GSTIN is invalid, cancelled, or suspended, your Input Tax Credit claim on their invoices will be rejected during GSTR-2B reconciliation
Avoid fake GSTIN fraud: Some fraudulent vendors provide fake GSTINs to collect GST without depositing it to the government. Verification catches these before payment
Prevent invoice mismatches: A wrong GSTIN on your sales invoice means the buyer's GSTR-2B will not reflect your invoice, causing disputes and delayed payments
Compliance with GST rules: Section 16(2)(aa) of the CGST Act requires that the supplier must have filed their GSTR-1 for the buyer to claim ITC. Verifying the GSTIN status helps ensure the supplier is an active filer
Accurate GST return filing: Wrong GSTINs cause mismatches in GSTR-1, leading to notices from the tax department and potential late fee charges

How to Use This GSTIN Verification Tool

This free tool validates the format and structure of any 15-digit GSTIN. It checks the state code, PAN format, entity number, default character, and check digit to confirm whether the number follows the correct GSTIN pattern.

Step 1: Enter the 15-digit GSTIN in the input field. The tool accepts both uppercase and lowercase letters
Step 2: Click the "Verify" button or press Enter to run the validation
Step 3: View the results showing validation status, state name, PAN, entity type, and a visual breakdown of each character
Step 4: If errors are found, the tool highlights exactly which part of the GSTIN is invalid so you can correct it

This tool validates the GSTIN format offline in your browser. For real-time verification of registration status, filing history, and business name, use the official GST portal at gst.gov.in. To apply verified GSTINs automatically on every invoice, try Petpooja Invoice.

GST State Codes List for India

The first two digits of every GSTIN represent the state or Union Territory where the business is registered. India currently has 37 state/UT codes used in the GST system. Knowing your state code helps you quickly validate whether a GSTIN belongs to the claimed location.

Major States: 01 Jammu & Kashmir, 02 Himachal Pradesh, 03 Punjab, 04 Chandigarh, 05 Uttarakhand, 06 Haryana, 07 Delhi, 08 Rajasthan, 09 Uttar Pradesh, 10 Bihar

Eastern & NE: 11 Sikkim, 12 Arunachal Pradesh, 13 Nagaland, 14 Manipur, 15 Mizoram, 16 Tripura, 17 Meghalaya, 18 Assam, 19 West Bengal, 20 Jharkhand, 21 Odisha

Western & Central: 22 Chhattisgarh, 23 Madhya Pradesh, 24 Gujarat, 25 Daman & Diu, 26 Dadra & Nagar Haveli, 27 Maharashtra

Southern: 28 Andhra Pradesh (old), 29 Karnataka, 30 Goa, 32 Kerala, 33 Tamil Nadu, 34 Puducherry, 36 Telangana, 37 Andhra Pradesh (new)

Others: 35 Andaman & Nicobar, 38 Ladakh, 97 Other Territory

Restaurant owners operating outlets in multiple states need a separate GSTIN for each state. The state code in the GSTIN must match the state where the business premises is located. Use the GST calculator to compute tax amounts once you have confirmed the correct GSTIN and applicable rate.

Types of GST Registration in India

Different businesses qualify for different types of GST registration based on their turnover, nature of business, and preference. The type of registration affects the tax rates, return filing frequency, and ITC eligibility.

Regular Registration: For businesses above the threshold limit (Rs 40 lakh goods, Rs 20 lakh services). Must file GSTR-1, GSTR-3B monthly or quarterly. Can claim ITC on purchases
Composition Scheme: For businesses with turnover up to Rs 1.5 crore. Pay GST at a flat rate (1% for manufacturers, 5% for restaurants, 6% for services). Cannot claim ITC. File quarterly GSTR-4. Most small restaurants opt for composition scheme
Casual Taxable Person: For businesses that occasionally supply goods/services in a state where they have no fixed place of business. Common for catering companies serving events in other states
Non-Resident Taxable Person: For businesses located outside India that occasionally supply goods/services in India. Registration valid for the period specified in the application
Input Service Distributor (ISD): For businesses that receive invoices for input services at their head office and distribute the ITC to branches registered in different states

The registration type does not change the GSTIN format. All types follow the same 15-digit structure. However, the registration type affects how the business files returns and whether they can issue tax invoices with ITC eligibility.

Free GSTIN Verification Tool