On Saturday night Swilly came from 2-0 down to beat Derry City 3-2 and take their place in the decider.
George Kelly and Ryan Doherty had Derry in front but Swilly hit back with two goals from Laurence Toland and the other from Calvin Mooney.
Under Jason Gibson Swilly are after their third piece of silverware in two seasons having lifted the Knockalla Cup for the last two years.
The defending champions Cockhill Celtic remain on course for the double after dumping Letterkenny Rovers out on Sunday at Leckview.
Rovers hit the front just before the break when Darren Mc Elwaine scored from the penalty spot after Gavin Cullen brought down Steve Okakpo.
Cockhill pulled off the result with two late goals, the equaliser on 86 minutes from Benny Mc Laughlin and then 4 minutes into injury time a header by Paul Mc Kinney gave the Inishowen side a dramatic 2-1 victory.
Letterkenny almost forced extra time when Okakpo came very close to scoring just before the whistle.
The Ulster Senior League Cup Final will be played on 16th August but before that Cockhill return to Leckview to play Letterkenny in a game which could see Celtic retain their League crown.