Three in five (60 per cent) of landlords said they would ask a tenant to provide a guarantor if their salary might affect their ability to afford the property.
Meanwhile, 16 per cent of landlords said they now require tenants to provide a guarantor, regardless of their salary.
A quarter (33 per cent) of tenants said they were asked to provide a guarantor in their most recent tenancy.
The study also polled tenants on their hopes of purchasing a home in the future.
Only 19 per cent of tenants said they were likely to buy a home in the next 12 months, but more would do so if they could.
In fact, 63 per cent of tenants said they would like to buy a home on the housing ladder but could not afford the deposit.