Engineers at Monzo have introduced a groundbreaking backup banking system—known as Monzo Stand-in—designed to operate independently and can be activated immediately during service outages. This innovative platform allows customers to perform essential banking functions such as making payments, withdrawing cash, freezing their cards, and sending or receiving bank transfers, even when the primary Monzo application is offline.
As the banking sector continues to evolve, the occurrence of outages has emerged as a critical issue for regulators and policymakers, particularly as a growing number of consumers shift to online banking. Recent data from the UK Government Treasury Committee indicates that nine prominent banks and building societies in the UK collectively faced at least 803 hours—over 33 days—of technical disruptions within the last two years.
For example, a recent three-day outage at Barclays resulted in 56% of online payment attempts failing due to significant performance issues within its mainframe processing. The bank has projected compensation costs ranging from £5 million to £7.5 million for affected customers as a result of this disruption.
In February, several UK banks, including TSB, Bank of Scotland, Nationwide Building Society, Halifax, Lloyds, and First Direct, experienced issues related to incoming and outgoing payments, further highlighting the vulnerabilities within the sector.
Monzo Stand-in operates on Google Cloud Platform, establishing a separate infrastructure that can seamlessly take over from Monzo’s primary AWS-based platform in the event of a significant incident. This backup system maintains crucial services such as card transactions, cash withdrawals, fund transfers, balance inquiries, and the ability to freeze or unfreeze cards.
The Monzo app periodically checks for the availability of the Stand-in functionality in the background. Upon activation, it switches to a simplified user interface that allows users to access essential features.
A spokesperson for Monzo commented, “With Stand-in, we ensure that our customers can continue to access vital services in the event of a serious outage—a scenario that is becoming increasingly common across the banking landscape. The effects of service interruptions on customers can be severe, especially when they cannot perform necessary banking tasks. To the best of our knowledge, we are the only bank offering such a solution.”
The Stand-in platform was first put to the test in August 2024 when Monzo faced a significant incident affecting its systems and payment processing capabilities. The bank reported that while the outage lasted approximately one hour, it promptly activated Monzo Stand-in to ensure customers could still access their funds.