Modes kept apart
Most shops record a day's takings as one figure, which hides the thing you actually need. Here every receipt carries its mode, so the evening position shows cash separately from UPI, card and bank transfer. Cash is the only line that has to match something physical, and once it is isolated a shortfall is obvious immediately. UPI receipts can be checked against the bank rather than assumed.
Counter expenses
Freight paid to a driver, loading charges, tea, a small repair — payments made from the drawer are the commonest reason a day does not tie. Recording each one takes seconds and produces two things: a cash book that closes, and a real monthly figure for what the shop spends. Most owners are surprised by that number the first time they see it, because it never existed anywhere before.
Bank alongside cash
Receipts into the bank, deposits from the counter and supplier payments by transfer sit next to the cash side, so the position is one view rather than two. Deposits are recorded as movements between cash and bank rather than disappearing from one and appearing in the other, which keeps both explicable. When a supplier says a payment never arrived, you have the date and the mode.
The evening routine
Check the day's receipts by mode, record anything paid from the drawer, compare the cash figure against what is physically there. Where more than one person billed, the figures break down by login — not out of suspicion but because a mistake is far easier to find the same evening than a month later. Shops that close the day properly stop having unexplained shortfalls within a few weeks.
When the day does not tie
Work through it in order rather than guessing. Check for a counter expense paid and not entered, which is the cause about half the time. Check whether a payment was taken by UPI and recorded as cash or the reverse, which is the next commonest. Check for a bill saved as paid when the customer actually took it on credit. And check for a deposit to the bank not recorded as a movement. Four checks, two minutes, and the difference is almost always one of them — provided you do it the same evening rather than a month later.