They were 65-54 winners against Peterborough & District, who had to be content with runners-up spot for the second year running.
Parkway were beaten 3-2 by Newmarket Avenue in the area final of the Bowls England Top Club competition.
Parkway brothers Ean and Tristan Morton are through to the last 32 of the Bowls England Family Pairs competition, defeating Chloe and Nicky Brett in the area final.
Meanwhile Parkway’s Nigel Eagle lost in the area final of both the national senior pairs and mixed pairs events, while Brian Martin suffered the same fate in the area senior singles decider.
Peterborough United's young stars shone to help secure a rare EFL Cup victory
Peterborough United should change their winning League One team!
Peterborough United manager was thrilled with his 'phenomenal', 'composed' and 'flexible' full debutants
Peterborough United's cross between CMS and Jack Marriott has seen a weight lifted off his shoulders
Peterborough United to face Stevenage in second round of EFL Cup
However, Sawtry’s Toby Furzeland has qualified for the last 32 of the national Champion of Champions.
The first of the three Peterborough Bowls League Cup finals takes place on Friday night with defending champions Burrows Court (formerly Conservative) facing Peterborough & District.