A GST number can be active and still cost you the credit.

How to read a GST number

A GSTIN is not a random serial. Every one of its fifteen characters is derived from something, which is why a fake GST number can be caught without looking anything up at all.

• Characters 1–2 — state code. The state of registration, not necessarily where the business operates. A company in Gurugram serving Delhi clients still carries 06, not 07.
• Characters 3–12 — the PAN. The business's own income-tax PAN sits inside its GSTIN, which is what ties the two identities together and lets you cross-check an invoice against a TDS certificate.
• The 4th character of that PAN — entity type. C is a company, P an individual or proprietor, F a firm or LLP. An invoice from "XYZ Private Limited" whose GSTIN carries a P in that position deserves a second look.
• Character 13 — registration count, but only on an ordinary registration. 1 for the first registration that PAN holds in that state, 2 for the second, and so on.
• Character 14 — registration type. Z for a regular taxpayer, but not always Z. See below.
• Character 15 — the check digit. Computed from the preceding fourteen using a modulus-36 algorithm. This is the one that catches invented numbers.

GST state code list — all 38 state codes, plus 97 and 99

The first two digits are the state code from the 2011 Census list. Two of them are legacy codes that are no longer issued to new registrations but still appear on older GSTINs, and two are not states at all.

Highlighted rows are legacy codes. 97 is used for the offshore area beyond a state's territorial waters — typically oil and gas operations on the continental shelf — and 99 for centrally administered entities.

Getting the state code wrong changes the tax itself

The state code is not cosmetic. It determines whether a supply is intra-state, attracting CGST plus SGST, or inter-state, attracting IGST. Charge the wrong pair and the recipient's credit sits in the wrong ledger, which is corrected by paying the right tax and claiming a refund of the wrong one — not by an adjustment entry.

What characters 13 and 14 actually mean

Most explanations say the fourteenth character is always Z. It is not, and a verification tool that insists on Z will reject perfectly genuine registrations — including those of government departments. These are the combinations in use.

The 4th character of the PAN

This single letter tells you what kind of person or body holds the registration, and it travels inside every GSTIN. It is the quickest sanity check there is: if the letter does not match the name on the invoice, something is wrong before you look anything up.

Why the check digit matters more than a search

Because the last character is calculated, any GSTIN that does not carry the right one was never issued. Somebody typed it wrong, or made it up. This page computes that digit in your browser before anything is looked up, so a fabricated number is rejected in an instant and it tells you which character should have been there.

That said, a valid check digit proves only that the number is well-formed. Someone inventing a GST number carefully could construct one that passes. Confirming that the registration exists, is live, and belongs to the business printed on the invoice still needs the lookup — which is the second half of what this tool does.

Active status is not the same as safe credit

This is the part that costs businesses real money. A GSTIN showing Active only tells you the registration has not been cancelled. Your input tax credit under section 16 of the CGST Act depends on something different: whether the supplier actually declared your invoice and paid the tax, which shows up in whether they are filing GSTR-1 and GSTR-3B at all.

A supplier can read Active for years while quietly stopping filing. Nothing about their registration status changes. Meanwhile the credit you claimed against their invoices is the thing at risk, and reversing it later carries interest. That is why the filing track record sits on this page next to the status, rather than being something you only discover during a reconciliation.

One caveat worth stating plainly, because it is easy to misread: a quarterly filer under QRMP legitimately shows two- and three-month gaps between GSTR-1 periods. A gap is not automatically a red flag — it has to be read against the taxpayer's filing frequency.

Taxpayer type changes what you can claim

The lookup returns a taxpayer type alongside the status, and the two are not interchangeable. An active registration of the wrong type can still mean you have no credit.

Two details that billing software regularly gets wrong

Delhi and Puducherry are not UTGST

Both are union territories, so software that switches on UTGST because the state code belongs to a UT will produce the wrong tax heads for them. Delhi and Puducherry have their own legislature, which means an intra-territory supply attracts CGST plus SGST. This tool flags it whenever you look up a 07 or 34 number.

State codes 25 and 28 are legacy

Code 25, Daman and Diu, merged into Dadra and Nagar Haveli and Daman and Diu — code 26 — with effect from 26 January 2020. Code 28 belonged to the undivided Andhra Pradesh, before Telangana took 36 and Andhra Pradesh took 37. A GSTIN carrying either is not automatically wrong, but it predates those changes and is worth confirming before you rely on it.

What to do when a supplier has stopped filing

Finding the gap is the easy part. What follows is a sequence, and the order matters because the remedies get more expensive the longer you leave it.

1. Stop treating the invoice as credit-bearing before the next return goes in. Claiming and reversing later costs interest; not claiming yet costs nothing.
2. Check it against your GSTR-2B, not 2A. 2B is the static, period-locked statement your credit is actually tested against.
3. Raise it with the supplier in writing. A supplier who has simply fallen behind will often file once told the payment depends on it. Keep the correspondence — it is the evidence of due diligence if the matter is ever examined.
4. Hold the tax component, not the whole payment, where your contract allows it. That keeps commercial goodwill while protecting the amount actually at risk.
5. Quantify the exposure across the vendor master, because a supplier who has stopped filing has usually stopped for every customer, and you are rarely carrying only one invoice.

Where the GSTIN turns out to be fabricated rather than merely delinquent, that is a different matter — fake invoicing is pursued seriously, and a fake GSTIN can be reported through the grievance route on the GST portal.

Finding a GST number from a PAN

Because the GSTIN is built from the PAN, the probable GSTIN for any PAN in a given state can be constructed exactly rather than searched for: state code, then the PAN, then the registration count, then Z, then the computed check digit. Where the business holds a single registration in that state — the common case — the constructed number is the real one.

What the arithmetic cannot tell you is whether that registration actually exists. So the Find GSTIN from PAN tab builds the candidate and then hands it straight to the verifier.

Frequently asked questions

The fifteenth character is a check digit calculated from the first fourteen. If it does not match, the number was never issued by GSTN and no search will ever find it. This tool computes it in your browser, so an invented GSTIN is caught immediately. A number that passes still has to be looked up to confirm it is live and belongs to the business named on the invoice.

Not from a GSTIN tool — the GST network does not expose a public name-to-GSTIN search. The reliable route is through the PAN: find the company on our company master data search, take its PAN, and build the probable GSTIN on the PAN tab here.

Not on its own. Active means only that the registration has not been cancelled. Credit depends on the supplier declaring the invoice and paying the tax, which is visible in their GSTR-1 and GSTR-3B filing record — shown here alongside the status.

No. A composition taxpayer is barred by section 10(4) from collecting tax and from issuing a tax invoice at all; they must issue a bill of supply stating they are not eligible to collect tax. If a document describing itself as a tax invoice shows GST from a composition dealer, the document is wrong and there is no credit behind it. Check the taxpayer type before you claim, not after.

No, and this is where most free checkers fail. Z is the default for a regular taxpayer, but D marks a TDS deductor under section 51, C a TCS collector under section 52, and combinations such as UN, OS, AR, RF and ES mark UIN holders, non-resident OIDAR suppliers, temporary IDs and e-commerce enrolments. A tool that insists on Z will reject genuine government department registrations.

2A is dynamic and keeps changing as suppliers file late; 2B is static and locked for the period, which is why it is the statement your credit is tested against. Verifying a GSTIN tells you the registration is genuine and whether returns are being filed; matching to 2B tells you whether your specific invoice reached it. You need both.

It has to match the state of that registration, which is not always where the goods ship from or where the head office sits. A business with registrations in several states will quote a different GSTIN depending on which state the supply is made from — and the state code drives whether you are charged CGST plus SGST or IGST, so a mismatch is worth resolving before payment rather than after.

Stop treating the invoice as credit-bearing and raise it with the supplier in writing before you pay the tax component. If the registration was cancelled or never issued, the credit is not available to you and reversing it later attracts interest. Fake GSTINs can also be reported through the grievance route on the GST portal. If you are already carrying credit against such invoices, get the exposure quantified before your next return goes in.

Registration details are cached for a short period so that repeated searches for the same GSTIN do not hit the network again, and the filing record is refreshed more frequently because it changes monthly. The format check, the state and PAN decode and the PAN-to-GSTIN builder involve no lookup at all, so they are always current and work even when the GST network is down.

Free, with no sign-up. We do not build a profile of what you search. Lookups of live registration details are cached briefly so repeated searches for the same GSTIN do not hit the network again.