Starting 16 September, your bank card will whisk you onto London's tube, trains, and buses via contactless payment.
The long-awaited arrival of contactless payment at the ticket barriers means you won't need an Oyster card to travel. Your bank card simply replaces the Oyster swipe card to touch in and touch out at the beginning and end of your journey, the cost of the journey automatically deducted from your bank or credit card balance.
Many newer debit and credit cards are contactless, which means they can pay for things wirelessly by simply tapping or holding them on a card reader, without the need to enter a PIN. There's a limit of £20 on purchases, but it saves time at the till both for you and for the retailer. If your card has a little Wi-Fi-style symbol on it you can use it without a PIN.
Currently, using London transport means using a swipe card, called an Oyster card, to enter stations or board buses. You can save a season ticket to the card, or top it up with pre-paid money that's automatically deducted after each journey on a pay-as-you-go basis. Once you hit a certain amount in a day, each successive journey is free as there's a cap on how much you're charged in a single day.
The advantage of using your debit or credit card is that unlike an Oyster card, you don't need to top it up with pre-paid money. That's handy for tourists and people who don't have an Oyster card, not to mention anyone who's lost their Oyster card.
London buses no longer accept cash, so contactless payment makes a good alternative. Buses have allowed you to pay with a contactless card for a while, but with no daily cap. Fortunately, contactless payments will have a daily cap, and a new weekly cap to boot.
As with Oyster, if you register you'll be able to go online, look at your previous journeys, and track your spending.
One potential headache with the new system is "card clash", when a ticket barrier detects both an Oyster card and a bank card. In such cases, the barrier won't open, which means you have to keep your Oyster and bank cards separate.