Independent Mortgage Advice Bureau Ltd, based in Watford, and The Financial Factory, based in County Down, have closed their doors.
In all the FSCS declared five firms in default last month.
Following the declaration of default, consumers could get back money they have lost as a result of their dealings.
A compensation of default means FSCS is satisfied a firm is unable to pay claims made against it. This paves the way for customers of that firm to make a claim for compensation.
Alex Kuczynski, chief corporate affairs officer at FSCS, said that it steps in to protect consumers around the UK when authorised financial services firms go bust.
He added: “We want anyone who believes they may be owed money as a result of their dealings with any of these firms to get in touch as we may be able to help you.”
In August, the FSCS declared two mortgage brokers in default, Cain Lambert Limited, formerly known as PAR Capital Mortgages, in London, and The Man for Mortgages Limited in Derbyshire.
Since it began in 2001, FSCS has helped more than 4.5m people paying out over £26bn in compensation.