Chancellor George Osborne's planned cuts to buy-to-let tax relief are the top worry for landlords thinking of selling up.
The squeeze on higher rate tax relief announced in the July emergency Budget is a factor for half of landlords currently looking to sell.
Those currently considering selling represent one in 10 existing UK landlords, with Osborne's tax reforms influencing their decision more than any other factor.
The new research from lettings agents Your Move and Reeds Rains also shows that landlords are pessimistic on rent rises, expecting growth to slow to just 1.4% over the next year.
Many fear letting out a property will become far less profitable when the reforms start to come into force in April 2017, and are now considering leaving the sector as a result.
This loss of enthusiasm is even dampening the optimism of the 31% of landlords who think that now is a good time to buy rental properties.
Two-fifths of UK landlords believe investing in buy-to-let property is more complicated than it was six months ago, due to more rigourous regulation as well as the forthcoming tax change.
Adrian Gill, director of Your Move and Reeds Rains, said: “Landlords could be forgiven for feeling a little deflated at the moment and its worrying to see this may motivate many to reconsider their investment.
“The Government’s tax changes appear to be making investing in buy-to-let less attractive because of the seemingly smaller profits margins on offer in the future."