A number of buy-to-let landlords will be forced to raise their rents to prevent their properties from being un-mortgageable amid rising interest rates, new research shows.

Nine in ten respondents to a new survey of landlords 600 have either already increased rents, or intend to increase rents, in part to meet mortgage affordability criteria, or risk being trapped on high rates, due to the Bank of England interest rate rise.

The study, undertaken by landlord insurance provider, Superscript, found that 50% of respondents already increased rents on their leased properties following interest rate rises earlier on in the year, with half of these intending to put rent up again.

Meanwhile, 40% of respondents said that while they have not yet increased rent but intend to do so if the BoE increases interest rates further, in part so that they satisfy their mortgage provider’s borrowing conditions.

Some 70% of these landlords said that they took this decision because it is the only way they are able to afford the increase in their mortgages resulting from the base rate rise. With more than half a million landlords already facing rent arrears due to a combination of the cost-of-living crisis and the collapse of housing support for tenants, this represents an affordability crisis for landlords across the UK. It is further emphasised by the fact that a majority – 58% – will have to seriously consider selling their leased property should interest rates increase further.

Despite the financial pressures, landlords – 37% of which can be said to be ‘accidental’, i.e. they became a landlord due to unexpected circumstances – are willing to work with tenants.

Half – 50% – of landlords surveyed indicated they would consider freezing rent should the tenants request to do so due to financial strains. Indeed, recent research by Shawbrook Bank suggested that one in twelve tenants have already had their rent reduced.

Cameron Shearer, CEO and co-founder of Superscript, said: “Landlords, like everyone else, are feeling the squeeze of the cost-of-living crisis. While Superscript’s research shows that a large majority of landlords are willing to help their tenants in the short-term with rent freezes or reductions, this is not financially sustainable for most landlords.

“If mortgage rates climb too high many will have to confront the choice of last resort, either increasing rents or selling property. With a shortage of rental supply, neither of these choices benefits the housing ecosystem, in which responsible landlords are a crucial and undervalued element.”