Petty Cash Controls for Small Teams That Actually Work

 

Petty cash has a reputation problem. It feels too small to matter, which is exactly why it becomes the messiest corner of the bookkeeping. A tin of cash in a drawer, receipts stuffed into an envelope, nobody quite sure who took what last Tuesday. The amounts are small, but the discipline it teaches, or the habits it lets slip, run right through the rest of the finance function. Getting petty cash right is cheap and easy. Leaving it alone is how fifty-pound mysteries become audit findings.

Run it as an imprest system

The imprest system is the single most effective control and it costs nothing. You set a fixed float, say 200 pounds, and top it back up to exactly that amount each time you reimburse. At any moment, cash in the tin plus receipts must equal the float. If they do not, something is wrong and you know immediately. The alternative, topping up random amounts whenever the tin runs low, means the balance drifts and nobody can tell whether a shortfall is theft, error, or just sloppy paperwork.

One custodian, and a lock

Name one person responsible for the tin and give them sole access. Shared custody is no custody: when everyone can take cash, nobody can explain a shortfall. The custodian keeps the tin locked when not in use and keeps the key on their person. In very small teams the custodian is often the person least senior, which is fine, as long as the responsibility is explicit and someone independent checks the tin periodically.

No voucher, no cash

Every payment out of the tin needs a voucher recorded at the time, not reconstructed at month end from memory. The voucher shows the date, amount, what it was for, and who took it. Pair each voucher with the receipt from the purchase. If there is no receipt, the person who spent the money writes and signs a note explaining why. The rule is simple and non-negotiable: no voucher, no cash. Once people learn the tin will not open without the paperwork, the paperwork starts arriving.

Count it, including by surprise

The custodian counts the tin weekly, and a second person counts it monthly. At least twice a year that second count should be unannounced. Surprise counts are not about distrust; they are the control that makes every other control believable. Each count is recorded and signed by both people, with the imprest reconciliation attached. A count that always balances is the best evidence your system works; a count that sometimes does not is the system doing its job by telling you something.

Set clear spending limits and banned items

Petty cash is for small, incidental spending: postage, milk, a taxi receipt, minor office supplies. It is not for wages, supplier invoices, or personal IOUs, ever. Set a per-transaction limit, commonly 25 or 50 pounds, and require anything larger to go through the normal purchase process. Ban personal advances outright, because a petty cash IOU has a habit of becoming a permanent loan. Put the rules on one page, pin it next to the tin, and make sure new starters read it in their first week.

Reconcile it to the ledger, properly

Petty cash is not a black hole in the accounts. Every reimbursement is posted to the nominal ledger with proper analysis: stationery to stationery, travel to travel. At month end, the ledger balance must agree with the tin count, and any difference is investigated, not plugged. Unexplained differences go to a suspense code with a note, and recurring differences trigger a review of the whole system. If your bookkeeper cannot produce the tin balance in thirty seconds, the controls are not working.

When to retire the tin altogether

Honest answer: many businesses no longer need petty cash at all. A prepaid company card or a low-limit credit card with per-user controls gives you the same convenience with automatic audit trails. If your tin mostly holds IOUs and the receipts arrive weeks late, replace it. For businesses that keep cash because of how they trade, tighten the controls above. Either way, the finance function should own the decision. Teams like Finex Outsourcing build exactly this kind of small-but-serious control into their financial accounting routines: imprest floats, independent counts, and ledger reconciliations handled as a matter of course. Petty cash is small money, but it is a good test of whether your controls are real. Pass the test and the big numbers tend to look after themselves.