Visa Europe has completed a major upgrade of its communications network, where it is using BT's Connect network to process approximately £1.7 million of payments every minute.
Managed by BT, the network provides connectivity for Visa Europe's card authorisation, clearing and settlement services, as well as linking 350 member sites in 37 countries across Europe.
It will also connect Visa Europe's corporate offices and provide remote working, mobile, messaging and video conferencing tools.
"Trust is very important to Visa Europe and to our customers. We work with providers that we can depend on to make sure our payments remain faster, smarter, convenient and secure," said Steve Chambers, chief information officer, Visa Europe.
"We choose to work with BT because we trust them to deliver on their promises. Their expansive global network supports our international connectivity needs and their focus on innovative technology and services aligns with our strategy."
BT and Visa Europe have been working together for the past 12 years and the network handled more than 14.3 billion transactions in the year up until June 2012.
"Visa is dealing with millions of people's payment transactions every single day, so their reputation for service, security and innovation is absolutely crucial. Visa Europe's continued trust in BT and the strengthening of our long term strategic relationship make us very proud," said Luis Alvarez, chief executive of BT Global Services.