Guides · GST
The GSTIN structure, explained
A GSTIN — the Goods and Services Tax Identification Number — is the 15-character number that identifies a registered business under GST. Each part of it means something, which is why it can be read rather than just copied.
What the characters stand for
A GSTIN has 15 characters. The first two are the state code, which tells you the state or union territory of registration. The next ten are the business's PAN, tying the GST registration to the same entity's income-tax identity.
The thirteenth character reflects the number of registrations the same PAN holds within that state. The fourteenth is a default letter, and the fifteenth is a check character used to catch typing errors.
Why reading a GSTIN matters
Because the state code and PAN are built in, a GSTIN can be sanity-checked before it goes on an invoice. A mismatch between the place of supply and the state code, or a PAN that does not match the party, is a signal to check the details.
Getting the counterparty's GSTIN right matters for both sides: it is what links an invoice to the buyer's ability to claim input tax credit.
How Lekha uses the GSTIN
Lekha generates GST-compliant delivery challans and tax invoices against a purchase order, with HSN, place of supply, and the right CGST/SGST or IGST split computed live, and gap-free financial-year numbering.
The supplier and buyer GSTINs sit on the tax invoice, and the state code helps confirm whether the supply is intra-state or inter-state.
Questions
- How many characters are in a GSTIN?
- Fifteen. They combine a two-character state code, the ten-character PAN of the business, and trailing characters for the registration count, a default letter, and a check character.
- What do the first two digits of a GSTIN mean?
- They are the state code, identifying the state or union territory where the business is registered under GST.
- Is a business's PAN inside its GSTIN?
- Yes. The ten characters after the state code are the business's PAN, linking the GST registration to the same entity's income-tax identity.
This guide is general information, not legal or tax advice. Confirm the current rules and your own circumstances for any specific case.