Calvert was sentenced by Judge Peter Testar at Southwark Crown Court, where he was convicted yesterday.
He is the fourth person to be jailed for insider dealing, which carries a maximum sentence of seven years, in the last 12 months.
Calvert was found guilty of obtaining confidential information about forthcoming takeovers and instructing a friend, Bertie Hatcher, to buy shares.
Calvert was found guilty on five counts of insider dealing. He made approximately £103,883 profit from the trades that took place between June 2003 and October 2004.
The prosecution involved a key witness and friend of Calvert, Bertie Hatcher, who has been fined £56,098 for market abuse.
Hatcher provided evidence in the trial having been involved in the illicit dealings and the FSA has published details of the agreement it made with himwhich led to his assistance in the prosecution of Calvert.
The FSA found that between 2003 and 2005 Hatcher had profited from inside information, using it to buy and sell about 420,000 shares in six companies. The fine represents the full disgorgement of his share of the net profit from these trades.
Nabarro Solicitors senior associate Roland Nattrass says: “Although the case is very likely to be appealed, this should be seen as a big victory for the FSA.
“Historically it has not had the strongest record of bringing insider dealing cases, which are costly and difficult to prove. This case was even more difficult to prove because the FSA was unable to say who the insider was.
“The victory will give a real boost to the FSA’s tougher enforcement agenda. A prison sentence is sure to make City professionals think twice about trading on inside information.”