The deals are available on Keystone’s standard and specialist buy-to-let mortgage ranges for loans between £350,000 to £1m.
The launch is to serve continued demand for houses in multiple occupation, multiple unit properties and standard properties on larger loans.
Two-year and five-year fixed rates are available up to 65 per cent loan to value.
David Whittaker, chief executive of Keystone Property Finance, said: “We have been working hard over the past few months to ensure we continue to support as many brokers as possible during a period of unprecedented uncertainty.
“As the mortgage market begins to bounce back, we’re pleased to be able to expand our range and offer competitive rates to help support buy-to-let landlords and their property portfolios.
“Through our new product range, we are aiming to provide landlords looking for larger loans with greater flexibility and choice, particularly as they look to capitalise on the recently announced stamp duty holiday.”
The stamp duty holiday until 31 March in England and Northern Ireland which applies to landlords and second homeowners as well as owner occupiers, has prompted several specialist lenders to bring back mortgage deals or expand their ranges.
Pepper Money has brought back its entire buy-to-let purchase range, Hampshire Trust Bank increased lending on its maximum 75 per cent loan to value, and Landbay increased its maximum lending limit to £1.5m. Meanwhile Foundation Home Loans cut rates on selected products.
Buy-to-let investors and second homes are still required to pay the three per cent additional homes levy throughout the stamp duty holiday.