Visa is investigating a "service disruption" after a stream of customers reported payment issues.
Downdetector which monitors outages on social media, recorded a spike in reports across multiple sites including Visa, eBay and PlayStation Network between 1pm and 4pm on Sunday.
Customers took to social media to vent their frustrations as transactions failed to go through.
One Twitter user complained: "Can’t make payments via Visa online in the UK. Just spoke to the Cooperative Bank and apparently they’re inundated with calls because the Visa system has crashed."
Another commented: "Can't pay my bills due to Visa being down in parts of the UK. Nice one."
In a statement, Visa said: "Visa is aware that a small number of cardholders are experiencing issues with making payments.
"This is as a result of a service disruption with a third party provider. We are working with our partners to investigate."
