Maria Michaela (31) posed as the heiress to a South African business fortune to claim eight loans for property in the capital, an investigation by City of London, police found.
She submitted heavily over-estimated prices for the houses and then defaulted on the mortgages, but was rumbled after using another fake ID to try to get more even more money.
She was jailed at Harrow Crown Court yesterday having previously pleaded guilty to fraud and conspiracy to defraud.
Detective Inspector Andy Fyfe, of City of London Police, said: "False identities and a corrupt property surveyor were the tools she used to make millions, turning herself into one of the -- if not the -- most prolific female fraudsters the UK has ever seen."
Between August 2007 and April 2008 Michaela, from south-east London, persuaded HBOS to give her four separate loans worth £10.5m to buy eight properties in the London area.
To support Michaela's application the bank was handed false valuations by a property surveyor, policeman's wife Mary-Jane Rathie, who received 'gifts' including a Bentley and a Range Rover.
Rathie was jailed for six years in July last year for five counts of fraud between May 2007 and June 2009 and a charge of concealing criminal property.
Her then husband, David Rathie, whom she divorced after their arrest, was a Metropolitan Police officer.
He was also charged with concealing criminal property, but was found not guilty.