Having been knocked out of the main competition by being beaten 21-12 by reigning champions Newcastle Falcons – Owen Giles and Jonathan Hampsey with the tries, Will Harries the conversion – the Academy-dominated Saints squad then set about trying to make the Plate final.
Newport Gwent Dragons and Leeds Carnegie were despatched in the quarter and semi-finals.
Harries' hat trick of tries was at the heart of the 29-14 win with Dave Ward and Hampsey also crossing the line.
Hampsey scored another two tries in the 25-17 semi-final win over Leeds.
Harries grabbed his fourth of the day and skipper John Brake and Paul Diggin sent Saints into the final.
Unfortunately Saracens, with a squad packed full of Sevens internationals, stood in their way.
They proved too strong for the Saints, and although Nick Greenhalgh capped his first appearance at Twickenham in the black, green and gold with a try, Saracens ran out 24-7 winners.
Harlequins won the main competition, beating the British Army 22-12.