Of those surveyed, 8% said their rental income had risen by 2%, with 4% saying it had increased by more than 6%.
There is a clear difference between the results from smaller scale and professional landlords. Nearly one in five smaller scale landlords (19%) reported rising rental income during the quarter, but the overwhelming majority (75%) said rents remained unchanged.
For professional landlords, however, it is a different picture, with almost a third (32%) saying their rental income had increased in the first quarter and only 2% saying that it had decreased in Q2.
Nigel Terrington, Paragon Group Chief Executive, said: "Results from our latest research shows that rental income has increased steadily during the second quarter. Landlords are continuing to experience high levels of demand for their properties so have been able to make small increases to rent levels, without making accommodation unaffordable.
"Demand for privately rented property shows no sign of slowing down with four out of ten landlords (40%) believing that tenant demand is either growing or ‘booming’, and will continue to do so for the next 12 months.
"However, it is increasingly important that finance for landlords becomes more readily available, so landlords can respond to growing demand for rental properties."
Have your say on this story using the comment section below