Every shop spends small amounts all day. The loader wants ₦1,500. The generator needs fuel. Someone has to buy nylon bags, pay the refuse collector, get water.

In most shops that money comes straight out of the sales drawer, and nobody writes it down. By evening the cash is ₦11,000 short of the sales total, and no one can say whether it was spent, lost or taken.

A petty cash book solves this with a separate small pot of money and one line per expense.

How it works

The method is called a float, or imprest, and it's simple.

  1. Decide a fixed amount for small expenses. Say ₦20,000. That's the float.
  2. Keep it in its own tin or envelope, separate from the sales drawer.
  3. Every small expense is paid from the float and written in the book.
  4. At the end of the week, add up what was spent and put exactly that amount back in.

So the float always returns to ₦20,000. And at any moment, the cash in the tin plus the total written in the book since the last top-up must equal ₦20,000. If it doesn't, you know immediately.

The format

DateDetailsVoucherReceivedPaidBalance

Details says what the money was for and who it was paid to. Voucher is the number of the receipt or slip that backs it up. Received is money put into the float. Paid is money spent. Balance is what should be in the tin.

A sample week

The figures are invented.

DateDetailsVoucherReceivedPaidBalance
1 OctFloat from owner20,00020,000
2 OctLoader, Sunrise delivery011,50018,500
3 OctFuel for generator026,00012,500
5 OctSachet water, 2 bags0380011,700
6 OctNylon bags042,2009,500
7 OctTop-up from owner10,50020,000

Spent in the week: 1,500 + 6,000 + 800 + 2,200 = ₦10,500. The owner counts the tin, finds ₦9,500, checks the four slips, and puts back ₦10,500. The float is ₦20,000 again.

Vouchers

Each payment needs something behind it.

Where a receipt exists, such as at the filling station, keep it. Number it and write that number in the Voucher column.

Where there's no receipt, as with a loader or a bag of water, write a small slip: the date, the amount, what it was for, and the signature of the person who received the money or the staff member who paid it. A cheap duplicate booklet works.

Keep the week's slips clipped together. When you top up, you're exchanging slips for cash: ₦10,500 of paper for ₦10,500 of money.

Seeing where it goes

After a month, group the payments under a few headings:

HeadingOctober
Fuel and power24,000
Loading and transport9,500
Packaging6,800
Water and cleaning3,400
Other2,300
Total46,000

This is where small expenses stop being small. ₦46,000 a month is over half a million naira a year. These figures also go straight into your monthly profit calculation, as shown in how to calculate profit and loss for a shop.

Rules that keep it working

Never pay expenses from the sales drawer. This is the whole point. The sales drawer should hold only the float for change plus the day's cash sales, so it can be balanced against the daily sales record book. If you truly must take from it, write the amount on that day's sales page as "paid out".

One person keeps the petty cash. They hold the tin, pay out, and write the lines. Someone else, usually the owner, counts it and tops it up.

Write the line at the time. Not at the end of the week from memory.

Set a limit per payment. Anything above, say, ₦10,000 needs the owner's approval first.

No loans. Petty cash is not for salary advances or for staff to borrow until Friday. If you allow an advance, pay it from elsewhere and record it properly.

Count it by surprise. Now and then, count the tin without warning. Cash plus slips should equal the float.

Top up by the exact amount spent. Rounding up hides small losses.

Choosing the float

Look at what you spent on small items in a normal week and set the float a little above that. Too small and you'll be topping up every other day. Too large and you have idle cash sitting where it can go missing.

If the float keeps running out early, either expenses have gone up or something is being paid from it that shouldn't be. The book will show you which.

Where it fits

A small shop's daily money sits in three places, each with its own record:

  • The sales drawer, checked each evening against the sales book.
  • The petty cash tin, checked against the petty cash book.
  • The bank account, checked against transfer and POS records.

Keep the three apart and each one can be proved on its own. Mix them and a shortage in any could be a shortage in all, which is exactly the situation that makes losses impossible to trace. More on that in how to stop staff stealing from your shop.