What caused the outage
Google said a "power event" hit the europe-west2-b zone, one of three zones in its London region. Google's UK cloud infrastructure is based in London, and no other region was affected. The trouble began at about 7am UK time. Google said the power issue was fixed by midday, but some services took longer to recover, and the incident was closed after nearly eight hours.
What was the impact
Customers of Revolut, Lloyds, Halifax and HSBC reported problems with their banking services. Revolut services such as ATM withdrawals, bank transfers and card top-ups were disrupted. Royal Mail, DPD, Rightmove and Screwfix were also affected, as was the video system used for remote court hearings across England and Wales. Revolut said customers' money and data were safe.
Response from regulators
The timing matters for regulators. In July, the UK named Google, Microsoft, Amazon Web Services and Oracle as critical third parties to the financial sector, which places them under direct oversight. The Financial Conduct Authority was engaging with Google and affected firms to understand the impact. Financial regulators in Europe have also questioned Google about the outage.
Exposed UK Dependence on a few cloud providers
Critics say the outage shows how exposed the country has become. Mark Boost, chief executive of UK cloud provider Civo, said that when one foreign provider can disrupt much of the digital economy, the system is not robust. He urged businesses to avoid vendor lock-in and to be able to move key systems between providers. One commentator described the reliance on two or three foreign firms for critical services as a catastrophe waiting to happen.
The concern is not new. One analysis found that around 95 per cent of the UK public sector depends on US cloud providers, and that 39 per cent of UK firms reported an outage linked to a large US cloud provider in the past year. The Cyber Monitoring Centre has also warned that using several providers does not remove the risk if critical systems sit in the same few regions.
The outlook
Google has apologised to affected customers and said it will investigate the cause, and services are back to normal. Yet the questions raised are likely to remain. Firms may be asked to show how they would cope if a whole cloud region failed. Policymakers must decide whether oversight alone is enough, or whether the UK needs more home-grown options. For now, many everyday services still rely on a handful of data centres, and one power fault was enough to show it.