The research found that the number of single property landlords making a loss doubled during the second quarter of 2012, with 16% of properties now losing money.

Also, 9% of these landlords experienced voids that lasted just over two months during the quarter.

Landlords with larger property portfolios fared better, with just 3% of those holding over 11 properties suffering a loss. 69% of landlords with 11-19 properties and 68% with 20 or more in their portfolio make a full time living from letting.

Mark Long, director at BDRC Continental, comments: “It is a tough time to be a private landlord if you have only one property in your portfolio.

“Over the last quarter profitability has clearly taken a dive. Regardless of their size, there is no question the private rental sector relies on private landlords and, whilst a third may aspire to increase their property portfolio, they will only be able to achieve this goal and add to Britain’s privately rented housing stock if they can make a profit from that one property.”