A successful group phase put United into the Central League Cup area final on Wednesday afternoon when they hosted Huddersfield Town at Frenchfield Park.
With two victories against Rochdale and an away win against the Cod Army under their belts, the Blues headed into what was always going to be an interesting test against the Terriers for the right to play Bournemouth in the national final.
United earned an early corner when Walker carried the ball into the box. His run was checked as he tried to step inside.
Carlisle came again and they took an early lead on six minutes when Scott snatched the ball off Jackson midway inside the visiting half. He forged on and into the box before cutting it back. Danny Devine marked his return from injury with a deflected strike that found the back of the net from close range - but Taylor Charters claimed the bragging rights as he got a final touch.
Another good run from Walker saw him take control with just one defender to beat. He dropped a shoulder but Chapman dropped low to parry.
The Terriers mounted a decent attack when Peplow crossed from wide. Headley jumped but his header went over the bar.
The home advantage was doubled on 19 minutes when Walker was chopped to the floor as he skipped past a challenge inside the area. Cedwyn Scott placed the ball and confidently stroked it into the bottom corner.
Huddersfield should have pulled one back moments later when Obiero ran across the face of the area with the ball at his feet. He had an empty net to aim at as he bypassed Norman, but he got his bearings wrong and he curled his effort wide of the upright.
Former-Blues loanee Obiero was close again when Jackson clipped a pass to the front stick. A firm header dropped the wrong side of the woodwork.
But the lively forward made no mistake at the third time of asking when a ricochet came his way. He got his head over the volley and rattled it into the bottom corner.
The Cumbrians settled things down again when Leslie lofted a high ball into the area. Chapman shouted for it, but he completely misjudged the flight and Cedwyn Scott was able to take it on his chest before picking his spot in the empty net.
First-year stopper Gabriel Breeze came on for the second half, and the Terriers were out of the kennels smartly as they pushed to get back into the game.
A series of corners were dealt with and United managed to keep their nets protected.
Cedwyn Scott was disappointed not to claim his hat-trick on the hour when Charters regained possession in a good area. He fed it to Walker, and a direct run was followed by a superb pass. Scott appeared to have the goal at his mercy, but he hesitated and his delayed shot was charged down.
Breeze was in action at the other end when he tipped a stinger from Diarra over the bar, but the visitors were right back in it when Elliott latched onto a low cross with his back to goal. He held his man off before sweeping it over the line.
The pace of the encounter remained high as the clock ticked down and Walker wasn't too far away with a 20-yard free kick that dipped over the wall, but also past the angle of post and bar.
United almost wrapped it up when Charters came away from a ruck with the ball just inside his own half. He ran on, bounced it off Fishburn, and was suddenly clean through. He went for power, and it rose just too high.
Peplow stepped inside to rattle one over the target on 90 minutes, and the Cumbrians saw the game through to claim their place in the National Final [v Bournemouth, date and venue tbc].
Carlisle United - Charters (6), Scott (19 pen, 32)
Huddersfield Town - Obiero (28), Elliott (71)
Huddersfield Town - Jackson (52)
Carlisle United - Norman (Breeze 46), Lightfoot, Barnes, Wilson, Leslie, Devine, Charters, Dixon (Walton 72), Walker, Scott (Fishburn 76), Bell. Subs - Swailes, Rooks.
Huddersfield Town - Chapman, Diarra, Daley, Ayina, Jackson, Austerfield (c), Peplow, Camara (Bright 68), Obiero, Daly, Headley (Elliott 35). Subs - Bellagambi, Kherbouche, McCamley.
Referee - Adam Nichol
Attendance - BCD