Santander for Intermediaries will decrease its residential retained property affordability rate, where the property is mortgaged and already let.
The changes will be made on 28 February.
The lender says the affordability rate of mortgaged and not let retained property will remain unchanged.
In addition, Santander for Intermediaries says that valuations will now be available on its Mortgage Application Tracking System (MATS).
Last week, the lender reduced rates on most residential new business rates by between 0.02% and 0.50%.
The lender’s lowest on-sale five-year remortgage fixed rate was 3.99% at 60% loan-to-value (LTV) with a £999 fee.
