Cain Lambert Limited, formerly known as PAR Capital Mortgages, in London, and The Man for Mortgages Limited in Derbyshire were declared as failed last month.
Four other financial advice firms – MML Administration Limited in Bristol, Chadkirk Wealth Management Limited in Staffordshire, Clearcredit Limited in Liverpool, and Abbot Insurance Brokers in Leicestershire also failed.
The FSCS declarations means customers left out of pocket by the companies could now get compensation.
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 your deposits, investments, home finance and insurance.
“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.”
Consumers making a claim for compensation can do so online with the FSCS or through the scheme’s customer services team on 0800 678 1100.
The FSCS has paid out more than £26bn in compensation since it was started in 2001.