Billing, Payments and Point of Sale (POS)
POS and billing controls
The exam tests accurate billing, tax treatment, payment reconciliation and return handling. A POS system records items through barcode or SKU, applies the correct price and tax, accepts payment and issues a receipt. A GST invoice normally shows supplier details, invoice number and date, customer details where required, description, HSN/SAC, quantity, taxable value, tax rate and amount, and total. Keep bill series sequential and reconcile cash, card, UPI and wallet collections at closing.
Payment modes
Cash needs a float and denomination count. Cards need authorization and charge-slip matching. UPI needs payment confirmation, not just a customer screenshot. Credit sales need customer approval and records. Failed payments must not release goods without a confirmed alternative.
Worked example
A product has MRP ₹1,000 inclusive of 5% GST. Taxable value = 1,000 ÷ 1.05 = ₹952.38; GST = ₹47.62. If ₹1,000 were treated as taxable value and 5% added, the bill would wrongly become ₹1,050. The reasoning: when MRP is inclusive, tax is extracted from the selling price, not added on top. Also check whether the item is exempt or at a different rate.
Traps
Do not sell above MRP for packaged goods covered by legal metrology rules. Do not ignore rounding and cash-shortage records. Do not issue duplicate invoices or back-date bills. Do not accept a UPI screenshot as final proof; verify the transaction. Returns need a reason, approval and stock adjustment.