The group revealed a £179m increase in its motor finance provisions, booked in the first quarter, taking the total set aside by the bank to £616m.

The UK arm of Spain’s Banco Santander reported a £1.2bn pre-tax profit for the nine months ending 30 September, down 6% on the same period last year. Net interest income rose 17% to £3.9bn following the acquisition of lender TSB, which completed in April this year. TSB has added £96m in pre-tax profit to Santander’s bottom line since it was included in its reports in May.

TSB also added £327m of operating costs and a £62m one-off “day one” credit charge. Restructuring and specific provisions rose to £495m from £134m a year earlier, a 269% increase, weighing on profits for the year to date.

The bank confirmed it did not challenge the Financial Conduct Authority’s motor finance scheme earlier this year, despite its criticisms of the scheme, adding that the outcome of remediation remained uncertain while other firms are challenging the regulator at the Upper Tribunal.

Santander has transferred the first 1,000 TSB staff into its operation as part of an expensive integration and restructuring process. Earlier this year, it started a small round of redundancies, which is expected to affect 33 staff.

The firm said in its latest statement: “We expect further cost efficiencies in 2026, driven by simplification and automation of our business, and integration of TSB.”

Meanwhile, the wider group recorded a €3.4bn attributable profit for the third quarter, down 2%, due to M&A-related charges. Underlying profit, which excludes these one-off items, rose 19% to €3.8bn, and nine-month underlying profit climbed 16% to a record €11.2bn. The group agreed to an interim dividend of 12.70 euro cents per share, paid on 2 November.

Santander expects the deal to place the group in the top 10 biggest retail and commercial banks in the US when measured by assets. Webster was valued at $75 a share in the deal, with $48.75 in cash and the remainder in stock.

The firm confirmed the acquisition was completed on 20 August, adding around €50bn of loans and €62bn of deposits to the group.

Santander UK chief executive Mahesh Aditya, said: “We made good progress this quarter, advancing the integration of TSB at pace and harnessing the strengths of both businesses to deliver the best for our customers.

“We also continued to deliver against our wider strategic priorities to deepen customer relationships and enhance operational efficiency, while leveraging Banco Santander’s global technology platforms and AI capabilities to provide the support our customers need.”