The Rogue Decimal Point

There is a particular sort of financial genius that involves making money from a credit card while never actually being in debt. It is not glamorous. It does not involve hedge funds. It involves paying for the weekly shop, collecting the points, and then moving the exact same money across from the current account roughly half a nanosecond later. The bank imagines it has lured you into its velvet-lined parlour. In reality you are there with a clipboard, timing them.

Over three or four years this has produced about a thousand pounds in rewards. Free money. Not life changing, but enough to irritate the institution providing it, which is satisfaction enough.

Unfortunately, the weak link in this otherwise elegant system is the human input device, namely me.

The problem is the decimal point. Or rather, the absence of it. A transfer of £65.50 becomes £6,550 with a single inattentive tap. £40.18 becomes £4,018. The app does not blink. It does not cough politely and ask whether I am quite certain I wish to move a month’s council tax in order to clear a sandwich. It simply obeys. Ruthlessly.

There is something uniquely deflating about realising you have just transferred several thousand pounds to your own credit card in a fit of typographical enthusiasm. The satisfaction of gaming the rewards system drains away rather quickly when your current account looks as though you have bought a modest hatchback by mistake.

Reversing the transaction via the app is, naturally, impossible. That would be convenient. Instead one must telephone the bank and explain, in a calm and measured voice, that no, one did not mean to move £4,018 to settle a £40.18 petrol purchase. Yes, it was a decimal issue. Again. No, I am not laundering money. Yes, I appreciate the call is being recorded for training purposes, which I assume means someone in a back office is enjoying this immensely.

The tone of the call handler is always professional, but one senses a flicker of suppressed curiosity. Who is this man who repeatedly overpays his credit card by the price of a Mediterranean cruise? Is he reckless. Is he confused. Or is he attempting some advanced financial manoeuvre that has gone badly wrong.

The truth is far less glamorous. I am trying to extract supermarket vouchers from a multinational bank without paying them a penny in interest, and occasionally I type like a distracted Labrador.

The real irritation is that the system is designed to tolerate incompetence in one direction only. If I had underpaid, interest would arrive with mechanical efficiency. Overpay by thousands and it requires a conversation, an explanation, and what feels suspiciously like gentle amusement on the other end of the line.

Still, I remain ahead on the scoreboard. The rewards continue. The bank continues to hope I will slip into revolving debt. And I continue to wage war with a decimal point that has cost me nothing except dignity and a few recorded phone calls that are probably still circulating in the staff break room.