I got a new debit card from my bank the other day, and put it in my wallet beside my Oyster card, which is an advance-paid card used like a season ticket in London to pay for public transport (bus, rail and tube journeys). Next time I hopped on a bus and touched my wallet to the reader to register my journey – and the reader complained that I had two cards. Uh-oh.
Eventually I took the Oyster card out of the wallet and touched it to the reader on its own – and that worked. Phew! But it wasted a bit of time. One of the points of Oyster is to save time: in Central London you may not pay with cash on the buses for this reason: all journeys must be paid for in advance. There are ticket machines by most bus stops, or you can get an Oyster card at tube stations.
Not wanting to waste time digging my Oyster card out of my wallet every time I want to use it, I tried putting a layer of tinfoil (aluminium foil) between the two cards: Oyster on one side of my wallet, debit card on the other: no good. It didn’t work. In fact, the reader on the bus couldn’t detect either card any more, even though the tinfoil was on the side facing away from the reader. While the physics of this might be interesting (sucking up the magnetic field lines or some such), it doesn’t solve the problem.
Looking about online for a solution, it turns out I have been lucky. If you present more than one contactless payment card to a reader at once, it may choose one at random and collect the payment from that. Now this would definitely not be a good thing. For one, my Oyster card gives me a discount for travel, since I buy my season tickets monthly in advance. A pay-as-you-go fare is much more expensive. Secondly, I want to know which bank account I am making any payment from anyway, to keep track of my money and to prevent unwanted overdraft charges. Furthermore, as this notice in an Underground station warns, on the Tube, your bank card could be charged, but the barriers to the underground still won’t let you in: you have to use your Oyster card. On the buses, I think, you can use a bank card if you want to, it is just more expensive (around double the cost). One bank does a combined card that works, I understand. That is, it charges you a flat £1.40 but the daily cap on fares won’t work (so you end up paying for all your journeys that day, unlike with a proper Oyster pre-pay card where your daily fare is capped and subsequent journeys are free).
It is also a problem that under ideal (or unlucky) conditions, these cards can be detected at a distance of up to 10cm, so you may need to keep the cards you don’t want to use well away from any readers. There are privacy and security problems with contactless payment cards anyway. Of course.
So when some other bank updates their card, I’m going to have three… will I need 3 wallets? Or, I suppose, I will just have to keep fishing the cards out of my wallet each time I want to use one, which almost defeats the object of the simpler payment method in the first place. OK, I don’t have to remember a PIN, but I still have to mess about with the card. For now, these seem to be the only solutions available.