The £15m deal will allow CTS to tailor the ticketing system to suit other world cities' transport systems. The income from this deal will be used to freeze fares across TfL services over the next four years.
London's Mayor Sadiq Khan said: “I made a firm commitment to sell Transport for London's expertise around the globe. We will use the income from those deals for further investment in new infrastructure and to freeze TfL fares.”
The contactless payment system was initially launched on London's buses in December 2012 and expanded to the city's Tube and rail services in September 2014.
To date, more than 500 million journeys have been made by more than 12 million credit and debit cards from 90 different countries, as well as using contactless-enabled mobile devices.
TfL's chief technology officer Shashi Verma said: “Contactless payments have completely transformed the way people pay for travel in London and this deal will allow other world cities to benefit from the hard work we put into making the system work for our customers.”
CTS also provides smartcard ticketing technology to several cities across the world, which include Sydney, Brisbane, Vancouver and Chicago.