If you are a TSB or Tesco Bank customer, you can either open the Wallet app and scan your card or simply authenticate the account you already have set up on your iTunes and App Store accounts. Both banks say they may send an authentication code to ensure Apple Pay is set up correctly, but the process shouldn't take more than five minutes.
It's interesting to note that while Tesco Bank is now on board, the supermarket itself hasn't fully committed to contactless terminals, with only a selection of its UK stores supporting tap-to-pay. One reason for this is that the contactless payment limit, which currently stands at £30, can restrict customers wanting to do a weekly shop. There is talk that Tesco may scrap the limit altogether, but for now only shoppers in London and other select regions can take advantage of it.
Following today's rollout, Barclays becomes the only UK bank to have committed to Apple Pay but not launched. Last month, the CEO of Barclays Retail Banking, Ashok Vaswani, confirmed that bank would enable Apple Pay functionality "very early in the New Year" after months of silence. Some customers have jumped ship while the bank works out its mobile payment strategy, which includes launching its own NFC payment service for Barclaycard customers with Android phones.