Mr Cohen has apologised to the Commons
A Labour MP will be stripped of a £65,000 allowance for retiring MPs after a "particularly serious" breach of the rules over his expenses claims.
Harry Cohen, MP for Leyton and Wanstead in east London, designated a house in Colchester, Essex, as his main home - despite renting it out to other people.
Now MPs have approved a report by the Commons standards and Privileges Committee into Mr Cohen's conduct.
He will lose the resettlement grant MPs are entitled to on stepping down.
Mr Cohen has already agreed to retire from Parliament at the forthcoming general election, expected in early May.
The Parliamentary Commissioner for Standards, John Lyon, found Mr Cohen had consistently claimed his Colchester house was his main home since buying it in 1998.
That allowed him to claim allowances worth more than £70,000.
But at the same time he let out the home to tenants on six-month leases, the report said.
Committee chairman Sir Malcolm Rifkind, a former Conservative minister, said they had "concluded that the Honourable Member's arrangements for his properties over a period of four-and-a-half years represented a particularly serious breach of the rules".
The committee acknowledged Mr Cohen faced particular difficulties as his wife had suffered a stroke in 2004.
The regular hospital treatment she needed in north London meant they could not stay in the Colchester home.
Mr Cohen has apologised to the House of Commons.
He has previously said he would abide by whatever decision the committee reached.