Global IT outage disrupts UK banks and other services

A worldwide IT outage sparked by a faulty software update from cyber-security firm Crowdstrike disrupted UK banks and other services on Friday 19 July, with customers of several providers still reporting problems accessing online and mobile banking the following Monday¹.

Over the weekend, Microsoft said 8.5m devices were affected, impacting flights, train journeys and healthcare services¹. Crowdstrike took responsibility for the problem and said a faulty software update was to blame, admitting the issue was caused by an update to its Falcon antivirus software, designed to protect Microsoft Windows devices from malicious attacks¹.

Among the banks affected, Santander reported disruption to online banking, cash machines, in-branch services and card payments, though its website said all services were up and running as normal by Monday 22 July¹. Sky News reported that Nationwide customers were having issues with online banking, and Downdetector showed that was still the case for some people on 22 July¹. According to Downdetector, Lloyds customers were still facing IT issues with online and mobile app services¹.

Metro Bank posted on X, formerly Twitter, to say customers may experience issues with their phone lines due to the global IT outage, and some payment services were also unavailable; reports on Downdetector show the situation had calmed by 22 July¹. HSBC was also hit, with online and mobile app services affected and customers facing issues with fund transfers, according to Downdetector reports, which showed a spike in reported problems at lunchtime on Monday 22 July¹. NatWest customers also reported trouble with online or mobile app services on Downdetector, which showed many customers still experiencing problems¹. The Independent reported that Barclays' digital investing platform Smart Investor was affected, with customers unable to manage their account in the app, online or over the phone¹.

CrowdStrike said a significant number of affected devices were back online after it identified the problem and deployed a fix¹. In an interview on NBC's Today Show in the US, Crowdstrike chief executive George Kurtz said:

Industry expert Adam Leon Smith of BCS, the Chartered Institute for IT, warned it could take "weeks" for all computers and systems to be fully restored, saying: "The fix will have to be applied to many computers around the world. So if computers are getting blue screens and endless loops, it could be more difficult and take days and weeks"¹.

Why it matters for households

Customers of the banks named above had difficulty reaching their money through online and mobile banking, cash machines, branches, card payments and phone lines during the disruption, and some were still reporting problems on Monday 22 July¹. Where a bank or building society was affected, Which? sets out steps for customers: contact the bank, gather evidence such as who you spoke to, the times and dates of the outages and receipts for any travel to a branch, then complain to the bank and ask for compensation to cover losses¹. If unhappy with the response, customers can contact the Financial Ombudsman Service, which can usually get involved 15 days after concerns have been raised with the bank, and sometimes sooner; it has official powers to help customers solve problems with their banks when they cannot agree, and will look at the facts, ask questions and make a decision on the fairest course of action¹.

What happens next

CrowdStrike said a significant number of affected devices were back online after it deployed a fix, but Kurtz said it could be some time for some systems that will not automatically recover, and Smith warned full restoration could take days and weeks¹. Which? said its list of affected providers may not be complete and that the story was updated after first publication on Friday 19 July¹.