Almost three quarters of portfolio landlords have found it more difficult to secure a mortgage since regulatory changes imposing tougher applications were introduced last September, research claims.

A poll of 817 landlords by specialist lender Foundation Home Loans, found that 70% of UK landlords with more than four buy-to-let mortgages said they had found obtaining finance a challenge since new Prudential Regulation Authority (PRA) rules came in last year bolstering the underwriting criteria for those renting out multiple properties.

As a result, 48% of landlords aware of the PRA changes think they will slow down the process of securing a mortgage, with two thirds of those who own 11 or more properties believing the range of mortgage products available to them will be reduced.

Almost a third, or 28%, believe the changes will make it more likely for their mortgage application to be rejected.

Jeff Knight, marketing director at Foundation Home Loans, said: “Whether these figures are to do with a natural period of adjustment or become the new norm remains to be seen.

“Nonetheless, in order to make this as smooth a transition as possible, brokers and lenders must work together to ensure things do not become unnecessarily challenging.”

Meanwhile, buy-to-let borrowing is increasingly being conducted through limited companies as landlords look to preserve the mortgage interest relief that is being scaled back for individual portfolios, a broker claims.

Analysis by Mortgages for Business, based on industry figures combined with its own, found 49% of all completions in the fourth quarter of 2017 were from limited companies.

This is up from 30% reported in the same period of 2016.

Of the total completions, 72% came from limited companies for landlords purchasing property, which bucks the trend in the wider mortgage market where most of the buy-to-let activity has been for remortgaging.

The report also reveals that the proportion of buy-to-let mortgages available to limited companies grew in the fourth from 21% to just under a quarter of all products, while average rates are now at around 4.2%, more than the 3.2% average across the whole market.

Steve Olejnik, chief operating officer at Mortgages for Business, said: “To help landlords determine whether using limited companies is the right strategy for them, we’ve been encouraging our clients to take professional advice.

“We will also continue to produce guides and webinars which explain how the tax and regulatory changes might impact their investments.

“The landscape of buy-to- let is changing and it’s important that landlords are equipped to traverse the terrain.”