TSB has upped the stress rate across most of its buy-to-let affordability criteria.

A new rate of 5.5 per cent, up from 5 per cent, now applies for remortgaging with no additional borrowing and all BTL mortgages with a fixed period of more than five years.

Previously the bigger rate only applied to purchases and remorgagings with additional borrowing or when converting residential property to BTL with a fixed rate of below five years.

In a note to brokers, TSB says that now, for all BTL mortgages, rental income is needed to cover the higher of either 145 per cent of the mortgage interest rate at initial product pay rate or 145 per cent of the mortgage interest at the new stress rate.

It adds that Dips for applications started before today will not be affected.