"The five-year fixed rate has been introduced in response to feedback from brokers."
In addition, the Society has reduced its three-year fixed rate from 3.99% to 3.49%.
The products are available up to 50% LTV for loans on properties across Scotland and carry a £995 fee.
The Society's retirement interst-only range is available to borrowers over 60 with no maximum age.
Paul Alexander, head of business development and sales strategy, said: "As one of the first lenders to launch a retirement interest-only mortgage, we have been delighted with the uptake to date. The five-year fixed rate has been introduced in response to feedback from brokers."
