Cornwall-based Premier Mortgage Centre was deregulated back in 2010 but it has taken until now for the firm to be classed as in default.
According to its Companies House details the business has repeatedly been threatened with being struck off in recent years, only for the authorities to then withdraw that action.
In its most recent set of accounts, the firm boasted around £300,000 in assets as of July last year.
The other firms to be declared in default by the FSCS included London-based Omega Financial Solutions, Bradford’s Breterac Limited and Leech & Burgess IFA, based in Plymouth.
A declaration of being in default means the FSCS is satisfied a firm is unable to pay claims for compensation made against it. As such, affected customers can instead make a claim with the FSCS.
Alex Kuczynski, chief corporate affairs officer at FSCS, said: “FSCS steps in to protect consumers around the UK when authorised financial services firms go bust. This vital service, which is free to consumers, protects deposits, insurance, investments, home finance and debt management.
“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.”