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How to Issue a Sales Invoice

Counter or back-office invoice with auto-GST.

6 min read Updated Jun 2026   How-To

Purpose

Issue a sales invoice that prices items from the rate standard, computes GST automatically, prints the customer copy, updates stock and posts the debtor and revenue journal — all in one save. This is the most-used recipe in the system, so it pays to understand both the fast counter flow and the slower back-office one.

Before you begin

  • Customer master exists (for B2B / credit sales). Walk-in / cash customers can use the generic Cash Customer.
  • Items in the invoice exist with the right rate standard and tax structure (see Configure Rates & Tax).
  • Stock available at the selling location (or back-order configured).
  • Counter is opened (for retail counters), or back-office voucher series is set up.

Steps

  1. Start → Purchase & Sales → Transactions → Sales Invoice. For counter use, the till screen opens directly with a new invoice.
  2. Pick the customer — use F4 to search by name, mobile or GSTIN. For walk-ins, leave as Cash Customer but capture mobile for the receipt.
  3. Add items — barcode scan, type the item code, or F4 search by name. Quantity, rate and tax populate from the masters.
  4. Apply discount at line or invoice level if needed — the rate-standard tax engine recomputes GST automatically.
  5. Pick the payment mode: cash, card, UPI, credit (for B2B), or split tender.
  6. Click Save & Print. The invoice gets a number from the voucher series, prints to the counter printer, posts the sale and stock-out journal, and (for credit sales) increases the customer's outstanding.
  7. Hand the customer copy across. For B2B, click Email PDF to also send a copy.

What success looks like

  • A printed / PDF invoice with the company header, GSTIN, line items and tax breakup is in the customer's hand or inbox.
  • Stock at the selling location reduces by the invoiced quantity (see How to Track Stock Movement).
  • The sales register and Day Book show the invoice; the trial balance moves accordingly.
  • For credit sales, the customer's outstanding increases by the invoice total.

Troubleshooting

"Stock not available" warning.
Negative stock is blocked by default. Either reduce the quantity, switch to a location with stock, or enable back-order on this customer if your policy allows.
Tax line shows zero.
Item has no tax structure. Set it in Item Master and re-add the line.
Customer's GSTIN does not print.
Customer master is missing GSTIN, or the invoice template does not include it. Update the master or pick a B2B template.
Printer prints garbage.
Wrong printer driver picked in the voucher series. Edit the series under File Management → Voucher Series and pick the right printer / paper size.

Tips

  • Train counter staff to always capture mobile number — it is the cheapest way to build a CRM list and to send the PDF copy.
  • For B2B, use the Email PDF button rather than printing and scanning — saves paper and the customer prefers it.
  • Warning. Never overtype the auto-generated invoice number. Voucher series enforce gapless numbering for GST audit.