Peter Gifford, 49, was convicted in his absence at Truro Crown Court of conspiring to launder $500,000 (Â£320,000) and sentenced to six years.
Gifford, of Budock, Falmouth and partner Penelope Lawton, 52, were previously convicted of mortgage fraud and sentenced to three years in jail.
Police said Gifford and Lawton were last seen travelling to France.
They are believed to be on the run with two teenage children and a European Arrest Warrant has been issued.
Police said the couple are understood to have left the UK just before a separate fraud trial in January and were last seen going on the Eurotunnel heading to France.
The couple were found guilty of three counts of fraud in their absence in January and sentenced to three years for each charge, to run concurrently.
In a series of frauds between 2002 and 2007 they made false declarations on mortgage applications to obtain Â£609,250.
The investigation into Gifford began when police were alerted to banking irregularities in his accounts and seized his computer in April 2011.
Police said Gifford had received $500,000 from an account in the US.
Officers traced the money back to a fraudulent investment scheme in Germany.
Police said he spent the money quickly on items including a new Range Rover and a luxury holiday to the US.
Investigators from Devon and Cornwall Police worked with the FBI and police in Germany during the five-year investigation.
Gifford was found guilty of money laundering in his absence on Thursday and sentenced on Friday.
An international money launderer and fraudster is believed to have fled the UK with his family, police have said.