A party’s GSTIN and state decide how GST is split on every bill you make for them. Getting this right means your tax is always calculated correctly.
What a GSTIN is
A GSTIN is the 15-character GST number of a registered business, for example
33AAAAA0000A1Z5. The first two digits are the state code — 33 is Tamil
Nadu, 29 is Karnataka, and so on.
When you type a GSTIN on the party form, Yojika reads those two digits and fills in the State (place of supply) for you. If you enter a GSTIN that is not a valid 15-character number, Yojika tells you so you can fix it — a wrong GSTIN would put the tax in the wrong place.
How tax is split: CGST + SGST vs IGST
Yojika compares your state with the party’s state (their place of supply):
- Same state (intra-state) — the GST is split into two halves: CGST and SGST. For example, 18% GST shows as 9% CGST + 9% SGST.
- Different state (inter-state) — the full GST is charged as a single IGST. For example, 18% GST shows as 18% IGST.
You can see this on any purchase bill’s Tax type line — it reads either Intra-state (CGST+SGST) or Inter-state (IGST).
Customers without a GSTIN
For an unregistered (B2C) customer, leave the GSTIN blank. In that case the State (place of supply) you set on the party is what decides the tax split. If no state is set, Yojika treats the sale as being in your own state (CGST + SGST).
Tip: Always set a customer’s state, even without a GSTIN, so inter-state sales are taxed as IGST correctly.