FA Cup holders Chelsea staged a spirited second-half comeback at Wembley, but it was not enough to prevent Manchester City from progressing into their second final in three seasons.
The encounter appeared to be over when Sergio Aguero headed City's second goal a minute after the half-time interval, but a Demba Ba volley and late onslaught from Chelsea so nearly forced extra time.
Samir Nasri had provided Manchester City with the lead in a first period completely dominated by Roberto Mancini's side, with the Frenchman making the most of a ricochet in the Chelsea box before lifting the ball past Petr Cech.
Chelsea entered into the break rattled but not damaged beyond repair, although a place in the final appeared to be beyond their reach after Aguero doubled the advantage so soon after half-time.
Gareth Barry stood a cross up into the Chelsea area, and Aguero spun off the shoulder of Branislav Ivanovic before directing his header beyond a static Cech and into the top corner.
Chelsea produced a stunning revival against Manchester United in their first encounter of the quarter-final, where they had been two goals down, and the Blues summoned the spirit of Old Trafford at Wembley.
Ba provided Chelsea with hope when he netted a wonderful acrobatic effort, before Juan Mata so nearly skipped past Costel Pantilimon in the Manchester City goal.
The young 'keeper, holding onto his place ahead of Joe Hart, then used all of his sizable frame to keep out Mata again, before David Luiz went close with a free-kick from distance.
Manchester City also continued to press forward, with Yaya Toure central to every surge, and could have netted a third goal were it for more decisive passing.
Chelsea had claims for a penalty dismissed as Fernando Torres tussled with Vincent Kompany, while Aguero was incredibly fortunate not to see red for an inexplicable stamp on Luiz.
Javi Garcia and Joleon Lescott were thrown on in the late stages tasked with closing out victory for their team, and Chelsea were unable to break down Manchester City's stubborn resistance as the seconds ticked away.
Manchester City will now face Wigan in the final of the competition, as Mancini looks to claim the third major title of his spell at the Etihad Stadium.