A dramatic penalty shoot-out victory over Manchester United at Old Trafford handed Sunderland their first trip to a major cup final since 1992 and their first in the League Cup for 29 years.
Here, we take a look at the Black Cats' route to Wembley.
SECOND ROUND - AUGUST 27, v MK DONS (H) 4-2
Sunderland came with 12 minutes of falling at the first hurdle as they trailed 2-0 the Sky Bet League 1 opposition at the Stadium of Light, thanks to Patrick Bamford and Izale McLeod. However, Jozy Altidore's first goal for the club, a double from substitute Connor Wickham and Adam Johnson's late strike completed a turnaround and handed then manager Paolo Di Canio his only victory of the season.
THIRD ROUND - SEPTEMBER 24, v PETERBOROUGH (H) 2-0
With Kevin Ball acting as caretaker manager, the Black Cats made light of the challenge offered by League One Posh as goals from Emanuele Giaccherini and Valentin Roberge either side of half-time saw them through.
FOURTH ROUND - NOVEMBER 6, v SOUTHAMPTON (H) 2-1
New manager Gus Poyet had to wait only four games for his chance to guide Sunderland into the quarter-finals as Phil Bardsley and Sebastian Larsson struck to make Maya Yoshida's late effort count for nothing.
QUARTER-FINAL - DECEMBER 17, v CHELSEA (H) 2-1 AET
Frank Lampard's goal took Jose Mourinho's men to within two minutes of the quarter-finals, but Fabio Borini's strike handed substitute Ki Sung-yueng the chance to win it with just seconds of extra time remaining.
SEMI-FINALS, FIRST LEG - JANUARY 7, v MANCHESTER UNITED (H) 2-1
The home side went in ahead at the break after Ryan Giggs could only bundle former team-mate Wes Brown's ball across goal into his own net. Nemanja Vidic levelled with a 52nd-minute header, but Borini ensured the Black Cats had a lead to defend at Old Trafford when he converted from the spot after Tom Cleverley had tripped Adam Johnson.
SEMI-FINALS, SECOND LEG - JANUARY 22, v MANCHESTER UNITED (A) 1-2 AET (AGG: 3-3. SUNDERLAND WIN 2-1 ON PENALTIES)
Former Sunderland loanee Jonny Evans dragged United back into the tie with a first-half header, but they needed a last-gasp Javier Hernandez strike to take it to penalties after Bardsley's 119th-minute goal looked to have booked Sunderland's trip to Wembley. But David Moyes' men wasted their reprieve in a dreadful shoot-out in which only Darren Fletcher was successful for the hosts, to allow Marcos Alonso and Ki to complete the job for the Wearsiders.