On the evening of Sunday 22 April 2018, a TSB customer in Hertfordshire opened the bank’s app to see how much he had spent at the pub the night before. His own accounts were there. So were three that belonged to a stranger: a £35,000 savings account, an £11,000 ISA and a business account.
TSB said that glitch lasted about 20 minutes. The rest lasted months. That weekend the bank had moved its 5.2 million customers off the systems of its former owner, Lloyds, and onto a new platform built by its Spanish owner, Sabadell. By Wednesday, TSB admitted that half its customers could not bank online. Business as usual returned only in December.
TSB’s view throughout, the Financial Conduct Authority later noted, was that it would not migrate until it was ready. A review by the law firm Slaughter and May, commissioned by TSB’s board, found that the date had come first.
In July 2015, the day after its takeover of TSB was declared unconditional, Sabadell had already picked a Sunday for the switch: 5 November 2017. It set that expectation without detailed knowledge of what TSB needed. TSB’s own master plan, nine months in the making, landed on the same Sunday. The reviewers called the timetable “ambitious and unrealistic” and said it set a pattern that stuck: choose the end date, then draw a plan to fit it.
The programme fell behind, and in September 2017 TSB postponed. At the board meeting before the announcement, the chair of the risk committee said she was not convinced the bank could deliver in the first quarter of 2018. TSB announced it anyway, nine days into replanning, before anyone had measured the work left. Two weeks later, a member of the risk team emailed the chief risk officer: “We appear to be repeating the previous approach of setting an end date and then fitting to it.”
The new plan had no contingency. The first quarter came and went, and the switch finally happened on 22 April. Other things gave way. Functional testing only finished because chunks of functionality were pushed past go-live, and the planned regression testing phase never ran. Of the four load tests for the app and internet banking, only app logins passed at the original target of 2,250 a minute. The targets were lowered, to 1,500 logins and 1,000 transactions a minute, and the summary of results did not make the change clear. In the first three days, combined logins ran above 1,500 a minute for almost 12 hours.
The load tests also ran on only one of the bank’s two data centres. TSB’s own analysis later named the way its apps behaved across the two centres as the main cause of what digital customers went through, which a one-centre test could not catch. The chief information officer accepted the supplier’s case for testing on one, and the decision appears in none of the minutes the reviewers saw. Before TSB, the reviewers noted, he had in effect run that supplier. Asked whether the board knew, he said it “was not the kind of decisions that we were sharing with the board.”
The board, meanwhile, was told that around 800 defects would go live. The real number was at least two and a half times that.
Paul Pester, the chief executive, stepped down in September 2018. In December 2022 the FCA and the Prudential Regulation Authority fined TSB £48.65 million. Four months later the PRA fined the former CIO, Carlos Abarca, £81,620. He had told the board the supplier was ready, the regulator found, without making sure TSB had got enough assurance from it.