When is IGST charged instead of CGST plus SGST?

When the place of supply is in a different state from the supplier, or for imports. IGST is a single levy at the full rate, later apportioned between the Centre and the destination state.

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GST Calculator

Add or strip GST, with CGST and SGST split out.

To add GST, multiply the base price by (1 + rate/100). To extract GST from an inclusive price, divide by (1 + rate/100) and subtract. On a ₹10,000 invoice at 18%, GST is ₹1,800 (₹900 CGST + ₹900 SGST) and the total is ₹11,800.

Your Inputs

Amount

₹

₹100₹10000000

GST rate

Amount entered is

Inter-state supply (IGST)

Total GST

₹1,800

Gap Analysis

Taxable value

₹10 K

GST

₹1.8 K

Taxable value

₹10,000

Invoice total

₹11,800

Formula used

GST = Base x rate; Base (from inclusive) = Amount / (1 + rate)

How this works

Composition scheme and registration limits

Registration is mandatory above ₹40 lakh turnover for goods (₹20 lakh for services, lower in special-category states). The composition scheme allows a flat 1% (traders) or 6% (services) on turnover but forbids charging GST or claiming input credit.

Frequently asked questions

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