Visa says a technical issue which prevented payments being processed has been resolved.
It meant customers in Ireland and Europe were prevented from using Visa for payments.
The company says the issue was the result of a hardware failure within one of its European systems - and not associated with any unauthorised access or cyber attack.
Image via @VisaNewsEurope on Twitter
Visa CEO Al Kelly said: "Our goal is to ensure all Visa payments work reliably 24 hours a day, 365 days a year.
"We fell well short of this goal today and we apologise to all of our partners and Visa account holders for any inconvenience this may have caused."
There were widespread reports of issues from Irish banks and businesses yesterday.
