Gross mortgage lending totalled £16.8bn in the year to Q3 2011 giving the lender an estimated market share of 16.5%, which Santander claims to be well above its natural stock share.
The lender said gross lending and market share have risen each quarter this year after a weak pipeline from Q4 2010 when pricing became less attractive for lower LTVs.
Net mortgage lending was £0.6bn in Q3 2011, up from £0.2bn in Q2 2011, with the average loan to value of deals at 65%.
The bank also reported a 9% decline of pre-tax profit to £1.6bn for the first nine months of 2011 compared to the same period in 2010, claiming this was due to higher regulatory and liquidity costs.
It said that if it excluded those items, its pre-tax profit would be up 10%.
Ana Botin, chief executive officer at Santander UK, said: “Santander UK has delivered another solid set of results despite the difficult market conditions.
“We have continued our strong support for UK homeowners and business. In the first nine months of the year our share of gross mortgage lending was c. 16%, which is well above our stock share, and means we are writing one-in-six UK mortgages.
“In the last two quarters, we have recorded positive net lending despite weak demand, while in SME lending, we are running ahead of our commitments made under the Merlin agreement. Lending to this vital sector was up 27% on the same point last year.”