Editor's note: This brief was summarised by The Property AI Newsroom from a report by Mortgage Solutions. Read the original article for full details.

Lloyds Leads Residential Lending, Santander Surges in Buy-to-Let Market

Lloyds Banking Group retained its position as the UK's largest lender for new residential mortgage business in 2025, advancing £52.2bn. Santander UK recorded the largest gain among the top six lenders, particularly in the buy-to-let (BTL) sector, where it nearly tripled its lending.

According to UK Finance data, Lloyds' market share in residential lending fell from 19.4% in 2024 to 18% in 2025, despite the increase in gross lending. Nationwide Building Society remained second with £49.4bn, and NatWest Group held third place with £35.1bn. Barclays, HSBC, and Santander UK followed, with Santander increasing its market share from 6.5% to 8.6%.

In the buy-to-let market, Nationwide Building Society remained the largest lender by gross lending in 2025, advancing £7.43bn. However, its market share declined from 20.2% in 2024 to 18.4% in 2025. Lloyds Banking Group stayed in second place with £5.5bn, while Coventry Building Society moved up to fourth after increasing its lending.

Santander UK was the most notable mover in the BTL rankings, jumping from 14th to 6th place after almost tripling its lending to £1.69bn. Its market share in BTL more than doubled from 1.7% to 4.2%. Other changes in the top 10 included TSB Bank climbing to 10th place in residential lending and Yorkshire Building Society dropping out of the BTL top 10.

These shifts in lending volumes and market share may be of interest to UK letting agents and inventory clerks, as lender activity can influence the availability of mortgage products and the dynamics of the rental market.