Case study · Finance
TSB: an IT migration that paralysed a bank
UK, 2018. A banking platform migration fails at go-live and disrupts services for months.
In one sentenceA go-live date is a decision, not a plan: TSB worked backwards from the date, and its customers paid for it.
- Sector
- Retail banking
- Country
- United Kingdom
- Date
- April 2018
- Duration
- Business as usual only by December 2018
- Regulatory outcome
- £48.65m fine (FCA and PRA, 2022)
Analysis based solely on public information. FZ Consultation was not involved in this incident and has no affiliation with the organizations named.
What happened
- 2015–2018
TSB prepares to move its services from the Lloyds platform to a new platform designed and run by a subsidiary of its parent, Sabadell.
- 20–22 April 2018
The data migrates successfully, but the platform suffers technical failures as soon as it goes live.
- Following weeks
Branch, telephone, online and mobile banking are disrupted; every branch and a large share of 5.2 million customers are affected.
- December 2018
The bank returns to business as usual.
- December 2022
The FCA and PRA impose a £48.65m fine. In 2023 the PRA also fines the former CIO.
What went wrong
According to the public sources listed below.
A schedule worked backwards
According to the regulators, the plan worked back from a target date instead of realistically estimating each stage, even after delays.
Reduced testing
The scope of non-functional testing for digital channels was reduced to one of the two data centres.
Weak supplier oversight
The regulators concluded the bank did not adequately manage the risks of its outsourced IT supplier, even though it was within the group.
Lessons for your organization
- 1
Plan left to right
Estimate each phase before setting a date, and honestly reassess after every delay.
Know: measure what stopping would cost - 2
Test under real conditions
Load, capacity and failover across every data centre before go-live, with a proven rollback plan.
Prove: rehearse before the real day - 3
Oversee critical third parties
An intra-group supplier is still a third party: ask for evidence, not reassurance. DORA and FCA/PRA rules require it too.
Regulations
Check on Monday morning
Three questions to put to your own organization this week. If you cannot answer one of them in five minutes, that is your first task.
- Take your next big change. Was each phase estimated before the date was fixed?
- Is there a rollback you have actually rehearsed, across every data centre?
- Ask your most critical IT supplier, even an internal one, for test evidence rather than reassurance.
Sources
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