The amount
It leaves the POS and lands on the terminal. Nobody retypes it, so nobody transposes two digits.
Payment
The payment terminal linked to the POS: what double entry really costs
Retyping an amount takes three seconds. And a mistake now and then, a discrepancy at closing, and half an hour spent working out why.
Two devices on the same counter, two ways of living. The standalone payment terminal waits for an amount to be dictated to it. The linked terminal receives it.
That is the whole difference, and it does not show at purchase: the two devices look alike, cost roughly the same and read the same cards. It shows in the evening, when it is time to count.
What the link changes, concretely
The receipt
It carries the method of payment without anyone having to remember it. Cash, card and mixed payments are all there in the evening, with nothing to reconstruct.
The tip
Added on the terminal, it comes back into the POS and appears in the report, instead of vanishing between the two devices.
The refund
It starts from the original sale, not from an amount keyed by hand into a device that has no idea what is being returned or why.
The split bill
Three cards on a table of six: the POS splits, the terminal charges, and nothing is counted twice.
Cashing up
This is where the gain really shows. What used to take twenty minutes and a missing receipt now fits on one screen.
The honest arithmetic
The gain is not measured in seconds. Retyping an amount takes three seconds, and nobody changes system for three seconds.
What costs is the mistake. One digit transposed on an amount, and there is a discrepancy at closing, half an hour spent tracing it, and sometimes a customer to call back. Once a week is enough to justify the link; once a day makes it obvious.
And there is the case people forget: the mistake that goes the other way. An amount keyed too low never comes back to complain.
The four points to check before buying
- Who supplies the terminal. Your bank, or the payment provider of your POS vendor. Both exist, they do not connect the same way, and they do not charge the same fee per transaction.
- Which model, exactly. “Compatible” is not an answer; a model reference is. The list of terminals that can be linked is published by the vendor, and it is shorter than it sounds in a sales meeting.
- Does your plan allow it? Integrated payments are not always included in the entry-level plan. It is one of the classic nasty surprises: the hardware is right, the licence does not follow.
- Is the current terminal on lease, and until when? A three-year lease decides the timetable far more surely than the choice of POS.
The hardware, family by family — including the payment terminal
And the cases where it is pointless
A roaming terminal that leaves the premises — a market stall, a delivery, a job at a customer's home — gains nothing from being linked to a POS that stays at the counter. Nor does a business where card payment stays marginal.
Better to say so than to sell a link that will not be used. Integration is justified by card volume and by how complicated taking payment is, not by principle.
A word on vocabulary, because it confuses everyone
In Spain, datáfono means the device that reads the card, and TPV the point-of-sale terminal. In France the first is called a TPE and the second a caisse.
The confusion is common, suppliers included: when someone offers you “a TPV”, ask whether they mean the sales software or the payment device. They are two purchases, two contracts and two different people to deal with — and it is precisely because they are separate that linking them is worth doing.
Do your terminal and your POS talk to each other?
The answer fits in one question: does anyone retype the amount?