Santander UK Q1 Profits Hit by Motor Finance Provision as TSB Acquisition Nears Completion

Costs were the standout positive. Operating expenses fell 7% to £638 million from £685 million, driven by simplification and automation. Santander’s cost-to-income ratio, or CIR – a measure of efficiency – improved to 55% from 60%.

That is the bit I like most in this release. If a bank can keep revenue broadly steady while cutting costs, that usually gives it more resilience. Santander is clearly trying to show that its investment in technology, automation and AI is doing more than generating nice press lines.

There was still some pressure on margins. Banking net interest margin, or NIM – basically the spread between what the bank earns on lending and what it pays on funding – fell to 2.22% from 2.30% a year earlier because deposit costs rose. Even so, it was slightly up on Q4-25’s 2.21%, and management expects NIM to be stable in 2026.

Mortgage growth, customer deposits and asset quality show the core Santander UK franchise is holding up

Lending growth was decent. Customer loans increased to £202.1 billion from £200.6 billion at the end of 2025, with mortgage balances rising to £170.2 billion from £169.0 billion. Gross mortgage lending reached £6.4 billion in Q1-26, up from £5.8 billion a year earlier.

Deposits also nudged higher to £190.5 billion from £190.2 billion, with customers continuing to move money into term savings products. That is pretty normal in a higher-rate world, although it does mean banks often have to pay more to keep depositors happy.

Credit quality still looks fairly solid overall. Santander said asset quality remains good, with the Stage 3 ratio improving to 1.15% from 1.17% at Dec-25. Stage 3 loans are the problem loans, so lower is better.

There are some early signs of normalisation in bad debt charges. Credit impairment charges rose to £73 million from £52 million, and the cost of risk ticked up to 11 basis points from 10 basis points at Dec-25. Management said this is trending back towards pre-pandemic levels, so it is not a shock, but it is a reminder that credit costs are moving in the wrong direction from ultra-benign levels.

Santander UK branch closures and digital investment cut both ways

Santander continues to reshape its branch network. In Q1-26 it announced the closure of 44 branches, with community bankers, Santander Locals and banking hubs used to maintain face-to-face support. The refreshed network will consist of 305 branches and 111 Santander Locals.

From a shareholder and balance sheet perspective, this should help efficiency. From a customer perspective, branch closures are always a mixed bag. Santander is trying to soften that by investing in app features, chat, telephone banking and more Work Cafés, but some customers will still see this as a downgrade.

TSB acquisition nears completion and could reshape Santander UK’s growth story

The other major theme is TSB. Santander said completion of the acquisition is expected imminently following recent regulatory approval. The agreed valuation is £2.65 billion, plus growth in tangible net assets up to completion, in an all-cash deal.

This is a big transaction. Santander says TSB brings about £34 billion of mortgages and about £35 billion in customer deposits. Combined, the two banks would serve nearly 28 million retail and business customers nationwide.

Strategically, this could be the real story here. Management is pitching TSB as a way to accelerate transformation, improve scale and unlock operational efficiencies through shared technology. That sounds credible enough, especially given Santander’s history of UK bank integrations, but integration risk is never zero. Big banking deals look smart on presentation slides; the hard part is making systems, staff and customers move across smoothly.

It is also worth noting that Santander UK has not yet set out its 2026-28 strategy and KPIs because those will come after TSB completes. So investors still do not have the full post-deal roadmap.

Santander UK capital, funding and outlook remain reassuring despite the profit hit

The balance sheet remains one of the more reassuring parts of this update. The CET1 ratio – a key measure of capital strength – stayed at 15.7%, while the UK leverage ratio was unchanged at 5.1%. Santander also had an LCR, or liquidity coverage ratio, of 162%, comfortably above regulatory requirements.

Funding looks sound too. The bank completed £6.1 billion of term issuance in Q1-26 and expects total issuance of £8.0 billion to £12.0 billion for 2026. Interestingly, the £650 million AT1 and £500 million T2 issued in the quarter were both fully subscribed by Banco Santander, which underlines support from the parent group.

The outlook, excluding any impact from TSB, is steady rather than exciting. Santander expects net lending growth to continue, NIM to be stable, costs to fall further through simplification and automation, and cost of risk to keep moving up towards pre-pandemic levels.

What this Santander UK RNS means for retail investors

My bottom-line view is fairly simple. This was a weaker headline quarter, but not a weak operating quarter. The motor finance provision did the damage, and that issue is still the main thing to watch.

If you are looking at Santander UK’s underlying banking performance, there were enough positives here to stop this from being a gloomy update. Costs are improving, mortgage lending is growing, asset quality is holding up, and capital remains strong. Add in the imminent TSB completion, and Santander UK is clearly trying to set up a bigger and more efficient business.

The catch is that 2026 is not going to be a clean, simple year. Investors will have to weigh regulatory overhangs from motor finance against the potential upside from the TSB deal. Right now, I would call this a resilient quarter with a nasty one-off sting attached.