The lender will offer members a 3.69% 2-year tracker shared exclusive available for both buy-to-let purchases and remortgages up to 60% loan to value.
Extra features include £99 cash back on completion, free standard legal services for remortgages and no early repayment charges.
The product comes with a 1% arrangement fee plus a £99 mortgage commitment fee.
Ying Tan, The Buy to Let Business managing director, said: “I am delighted to welcome Principality onto our panel. Principality has an impeccable track record of excellent service with market leading innovative products particularly at the lower loan to value.”
Jason Newsway, head of intermediary sales at Principality, said: “We have been working with Ying and his team for some time and have been extremely impressed by their market knowledge and the overall expertise in the buy-to-let market. We are delighted to be part of this proposition and wish them every success.”