Around 440,000 landlords who pay the basic rate of tax will be forced into a higher tax bracket from Apriil next year, according to the National Landlord Association.
The changes, to be fully phased in by 2021, will mean landlords will no longer be able to deduct mortgage interest payments or any other finance-related costs from their turnover before declaring their taxable income.
Currently, mortgage interest payments are one of a number of expenses that landlords can deduct as a business cost.
The NLA is lobbying housing and planning minister Gavin Barwell on the issue.
NLA chief executive Richard Lambert says: “When the Government announced these changes last year, it claimed they would only hit a small proportion of higher-rate tax payers. We now know that is complete tosh.
“The Government must look to amend these tax changes and minimise the impact on landlords and their tenants – something that could easily be achieved by applying the rules to only new loans written after April 2017.
“Unless this happens, landlords will face an impossible decision of whether to increase rents and cause misery for their tenants, or to sell-up, and force their tenants to find a new home.”