The proportion of former rental properties going up for the sale market is at its highest level on record, according to Rightmove data.
It shows that 18% of properties now for sale were previously on the rental market, compared with 8% in 2010.
In London, 29% of homes for sale were previously for rent.
The previous five-year average for homes moving from the rental to sales market in Britain is 14%.
The number of new properties being listed for sale is 14% ahead of last year.
Rightmove property expert Tim Bannister says: “In recent years it has become more attractive for some landlords to leave the rental sector rather than to continue to invest in it, due to rising costs, taxes, and legislation.
“A healthy private rented sector needs landlord investment to provide tenants with a good choice of homes.
“We’ve seen over the last few years how the supply and demand imbalance can contribute to rising rents, so there is a worry that without encouragement for landlords to stay in rather than leave the rental sector, it is tenants who will pay the price.
“However, despite the trend of more landlords choosing to sell up, it doesn’t appear to be a mass exodus, and we will need to monitor the longer-term impacts of what happens to the rental supply that is put up for sale.“For example, these homes could provide first-time buyers with more choice.
“They might also be purchased by other landlords and put back into the rental market, which would signal a changing of the guard rather than a complete exit from landlords.
“In any case, we hope the government is considering ways it can support landlords and the private rented sector ahead of the Autumn Statement.”
London estate agent Benham and Reeves’ director Marc von Grundherr says: “The potential equalising of CGT [with income tax rates] is, of course, a concern for many landlords.
“If the Labour government was to follow through with it, it could make for a significant increase in the tax paid by the average landlord when the time did come for them to exit the sector.
“This would be yet another blow to those who provide vital housing stock that is sorely needed within the rental sector, following a string of legislative changes already introduced in recent years to dent profitability.
“Despite this, we’re simply not seeing the exodus of landlords that is so often reported, as despite such changes, buy-to-let remains a strong investment.
“It’s certainly one that most take with a very long-term view and they expect ups and downs, but generally speaking, the returns are consistently good.”
