The lender — which owns Royal Bank of Scotland, Coutts and Ulster Bank — said: “In line with wider market trends, new business in the mortgage portfolio was accelerated in the first quarter, ahead of stamp duty changes introduced on 1 April 2025.” 

In the second quarter of the year, the bank’s mortgage balances rose by £1.4bn. 

During the six-month period, the lender added one million customer balances from Sainsbury’s Bank, and has continued to improve our customer proposition, including the launch of our family-backed mortgages”. 

NatWest bought a large proportion of the assets of Sainsbury’s Bank for £125m last June, including personal loans, credit card balances, and customer deposits. This sale did not include home loans, which the supermarket sold to the Co-operative Bank for around £464m in cash in August 2023.   

NatWest said its mortgage loan book came in at £213.3bn in the period, up 1.4% since the start of the year, with landlord loans accounting for £21bn. Mortgages make up 51% of its overall lending. 

It reported an average loan-to-value of 56% across its mortgage portfolio, which was “stable year-on-year”. 

The lender added that arrears levels of more than three months “remain low” at 0.63% against an industry average of 0.89%. 

NatWest also announced a £750m share buyback and raised its guidance for the year as the bank reported its first results since returning to full private ownership in June, almost 17 years after it received a £45.5bn government bailout at the height of the financial crisis. 

It posted pre-tax profits for the second quarter, which beat analyst expectations, although they were broadly flat at £1.8bn compared to £1.7bn a year before. Analysts had expected £1.6bn in the three months to June. 

NatWest chief executive Paul Thwaite said: “With positive momentum in our business, we are ambitious for the future and see clear opportunities for further disciplined growth.”