Ask a shopkeeper what they sold last month and you will get an answer. Ask what they bought and you will usually get a drawer of paper. Both sides are equally part of the books; only one of them gets kept properly, and it is worth being honest about why.
Why sales get recorded and purchases do not
A sale has a customer waiting for a bill. That external pressure is what makes the record happen. A purchase has nobody waiting — the supplier already has their copy, and the bill you were handed sits in a bag until someone asks for it. Nothing forces the entry, so nothing happens.
What that costs you
- Input credit you are entitled to and cannot substantiate, because the bill is gone.
- A profit figure that is wrong in the flattering direction all year.
- No idea what you actually owe suppliers, until one of them calls.
- A reconstruction job every filing period, done under time pressure, which is where mistakes enter.
Purchase order versus purchase bill
They are different documents doing different jobs and conflating them is common. A purchase order is what you asked for — it commits nothing financially and exists so that what arrives can be checked against what was ordered. A purchase bill is what you were actually charged, and it is the one that carries tax and enters your books. BizGST Pro keeps them separate, and marks an order received when the goods turn up.
Unpaid bills are a number you should be able to see
Most owners can tell you what customers owe them and cannot tell you what they owe suppliers. Both are cash-flow facts. If your software shows total payable and unpaid bills at a glance, that half of the picture stops being a surprise.
The habit that fixes it
Enter a purchase bill the week it arrives, not the week it is asked for. That is the whole discipline. It is unglamorous, it takes a couple of minutes per bill, and it removes the single largest source of filing-season panic — which is not complexity, it is reconstruction.
On input credit specifically
Whether a particular purchase is eligible, and what conditions attach, is a matter of the rules as they stand — check the GST portal or your accountant. What no rule can help with is a bill you no longer have. Keeping the record is the part that is entirely within your control, and it is the part most often skipped.