GSTR-1
Monthly or quarterly GST return that reports all outward supplies (sales) made by a registered business under the CGST Act.
GSTR-3B
Monthly self-assessed summary GST return that captures outward tax liability, input tax credit, and net tax payable.
IRN (Invoice Reference Number)
Unique 64-character hash generated by the Invoice Registration Portal (IRP) for every B2B invoice issued by businesses above the e-invoicing turnover threshold.
HSN Code
A 4-, 6-, or 8-digit product classification code used worldwide and required on Indian GST invoices to identify goods and their applicable tax rate.
ITC (Input Tax Credit)
The mechanism that lets a GST-registered business set off the GST it paid on purchases against the GST it owes on sales, reducing cash outflow.
RCM (Reverse Charge Mechanism)
A GST provision that shifts the obligation to pay tax from the supplier to the recipient — common for transport, legal, and unregistered-vendor purchases.
GSTIN
15-character alphanumeric identification number assigned to every GST-registered business in India, encoding state, PAN, and registration entity.
E-way Bill
Mandatory electronic document for any movement of goods worth ₹50,000 or more — generated on the e-way bill portal before transport begins.