The five-year fixed rate, which is available up to 75 per cent loan-to-value, has an interest rate of 3.39 per cent.
It comes with a product fee of 1.5 per cent, one free standard valuation, and no further application fee.
The lender said it believed the new deal would appeal to portfolio landlords who want to limit their upfront costs, particularly those looking to make changes to multiple properties across the portfolio.
The move follows the launch earlier this month of a five-year fixed remortgage product for the same type of borrower.
Jeff Knight, director of marketing at Foundation, said the lender was seeing strong growth in demand from portfolio landlords, who are prioritising keeping upfront costs to a minimum.
He continued: “For professional landlords, and their advisers, using a lender that is immersed in the sector and understands their specific – and often complex – needs is absolutely vital. This is why we have the specialist knowledge and drive to deliver what landlords need in order to help them develop and grow their portfolios.”