The 2-year discount is 3.79% with an application fee of £199 and a completion fee of £800 which is added to the loan while the fixed alternative is 3.43% with a 2% completion fee and £199 completion fee.
Chief executive Gev Lynott said building societies, particularly some of the smaller ones, should not be overlooked by private landlords when they investigate their mortgage options.
He said: “Whilst we are based in Mansfield we offer these mortgages on properties throughout England and Wales.
“Smaller building societies frequently offer terms that are extremely attractive when compared to national lenders with the added bonus that they can be more flexible on underwriting issues.”
Lynott said the Mansfield does not use automated credit scoring which allows it to get a closer understanding of each case and offer a more flexible underwriting approach.
There are also 3-year fixed rate options available from 3.75%.
All buy-to-let products are available either direct from the society or from professional intermediaries for new mortgages or remortgages up to a maximum loan to value of 70%.