Orville Wright, 26, had agreed a pounds 4,000 fee from his intended victim's former lover for carrying out the murder - with the promise of an extra pounds 1,000 if he did it right, an Old Bailey court was told.
Former legal clerk Wright, his face masked by a balaclava helmet, and brandishing a knife, broke into the woman's flat in Tottenham, north London.
But after talking to the intended victim. Theresa Pitkin, 30, a mother of three, he told her he could not go through with it. Ms Pitkin had told the court: "I thought he was going to rape me but then he told me he had been contracted to kill me."
At first Wright said he had been hired by a friend of her ex-lover's to cripple her. But then he said the ex-lover, 30-year-old David Martin, had contacted him and ordered her murder.
Mr Martin has not been charged and denies any involvement. Ms Pitkin kept Wright talking and eventually he lost his nerve and decided not to go through with the killing.
Mark Hill, prosecuting, said: "He was a hit-man about to carry out the killing and that he did not do it is a great relief to Miss Pitkin and others. He is a hitman who lost his nerve."
Wright, of Bruce Grove, north London, was found guilty last month of aggravated burglary with intent to cause grievous bodily harm.
He said he went into the flat to warn Ms Pitkin about the contract killing but never intended to carry it out.
Mark Pallenghi, defending, said Ms Pitkin and her mother had forgiven Wright - and even offered to buy a ticket so he could return to Jamaica.
Judge David Murchie said he had reduced Wright's sentence because of the unusual circumstances of the case.
The judge told Wright, who worked in Jamaica for seven years as a legal clerk: "I can't forget her words that you were a hit-man who lost his nerve."Reuse content