Chasing the Bay of Plenty total of 147 for seven, they were bowled out for 94 in 19.2 overs.
Parminder Kulaar made 21 for Poverty Bay batting at No.4.
Poverty Bay opening bowler Jimmy Holden took 2-21 from his four overs and Drew Brierley took 2-24.
BoP No.3 Bharat Popli top-scored with 49 from 34 balls and he hit seven fours.
Poverty Bay were due to have two more T20 matches today but MetService was forecasting rain.
Bay of Plenty 147-7 off 20 overs (Bharat Popli 49; Jimmy Holden 2-21, Drew Brierly 2-24) beat Poverty Bay 94 off 19.2 overs (Parminder Kulaar 21; Tim Pringle 2-18, Jacob Logan 2-19, Craig Baldry 2-30).