Yesterday Chancellor George Osborne announced that stamp duty will be hiked by 3% from April 2016 in the Spending Review and Autumn Statement.
A Treasury spokeswoman said: "Corporates or funds with more than 15 residential properties won't be liable for the 3% increase.
"That's the overarching strategy but more details will be released in due course."
Ray Boulger, senior technical manager of John Charcol, said: "It will be a silver lining for some landlords, though I suspect only 2% to 3% have more than 15 properties.
"If you qualify it's a big help. What it does do is give larger landlords a competitive advantage. If you can benefit from the exemption because you already own 15 properties then you can afford to pay more for properties.
"The Chancellor has said he wants to change the balance between landlords and homeowners, but this will change the balance within the landlord sector."
