A purchase in PharmaPOS represents one supplier invoice. Each purchase line auto-creates or updates a batch of the corresponding product. Get purchases right and the rest of your stock, GST, and margin math is right by construction.

Recording a purchase

Go to Purchases → New purchase.
Pick the supplier. If they don't exist yet, add them in the same drawer — GSTIN, address, contact.
Enter the supplier invoice number and date at the top. This is the number your supplier issued — not something PharmaPOS generates.
Add lines: product, batch number, expiry, quantity, purchase price (pre-GST), MRP, GST rate.
Save. Batches are updated, supplier ledger is credited, stock is available for sale immediately.

What each field does

Supplier invoice #	Free text. What the supplier printed on their bill.
Batch #	Free text. Manufacturer batch, exactly as printed on the strip.
Expiry	Month + year (MM-YYYY). Used for FEFO picking and expiry reports.
Purchase price	Landed cost, pre-GST. Drives margin math and the purchase register.
MRP	Printed on the strip. Sale price defaults from here but can be lower.
GST rate	5, 12, 18, 28. Used both for input tax credit and outbound invoicing.

Editing & viewing a purchase

Every purchase has its own page at Purchases → click a row. You can view the full line-by-line breakdown, print the internal record, or download it as PDF for filing.

Cancelling a purchase

If you keyed a purchase in error, open it and click Cancel. What happens next depends on whether any stock has moved:

If no stock has been sold, the batches are archived and the supplier ledger is reversed.
If any unit has been sold or returned, cancellation is blocked. You must issue a purchase return to the supplier instead.

Purchase returns

From an existing purchase, click Create return, pick the lines and quantities, enter a reason. Stock is deducted from the exact batch; supplier ledger shows a debit. The return has its own serial and is inspection-ready.