NFC readers in 46 travel-centric locations to start.
WHSmith is a veteran of the UK high street, specialising in books, stationery, cards and the stuff that goes in pencil cases.
It's now teamed up with Streamline and Visa Europe for the trial, which will be initially be available at locations such as Heathrow, Gatwick, Stansted and Mainline Railway Stations.
The trial will mean customers with NFC enabled credit cards will be able to wave them in front of Visa payWave readers to pay for items under £15 (rising to £20 from June 1st).
So, no, it's not specifically mobile. But clearly it will work with any NFC-enabled mobile device that's embedded with a PayWave compatible wallet.
WHSmith has over 1,000 stores and is the first large bookseller, stationer and newsagent to adopt contactless technology in the UK.