Payleven, one of several European firms hawking an app and dongle-based system for turning smartphones into card readers, has been fully authorised by the UK's Financial Services Authority as a payment institution.
The German-headquartered start-up is the first of its kind to secure approval from the UK's chief financial watchdog, enabling it to contract directly with its customers.
The arrangement effectively covers the firm - which currently operates in Italy, Poland and the Netherlands, as well as Germany and the UK - across Europe.
In addition, payleven has become part of MasterCard's mPOS program, a project designed to ensure mobile point-of-sale providers adhere to the best industry practices.
Alston Zecha, co-founder and COO, payleven, says: "Being part of the FSA and MasterCard's mPOS program acknowledges our hard work to offer the easiest and safest mobile payment solution."
Last year the company was the first to introduce a chip and PIN, rather than swipe, dongle for mobile card readers but has since seen rivals strive to catch up.
IZettle - which has approval from Sweden's financial watchdog and is part of the mPOS programme - recently rolled out its chip and PIN offering, while American giants PayPal and Intuit are also now knocking on the European door.