Kate Pulford thumped 89 off 97 balls, including two sixes, while 16-year-old schoolgirl Aroha Northover contributed 53 as Central Districts overcame Wellington's 182 for five in the 44th over on Saturday.
Wellington's score was based around half centuries to Anna O'Leary, who made 54, and Jane Hunter-Siu, who made 50.
O'Leary's innings lifted her tournament aggregate to 404 runs at an average of 135.
Canterbury won the play-off for third when Haidee Tiffen struck an unbeaten 98 to guide her side to a four-wicket victory over Northern Districts.
Scores:
Final: Wellington 182-5 (A O'Leary 54, J Hunter-Siu 50) lost to Central Districts 184-6 in 43.5 overs (K Pulford 89, A Northover 53) by four wickets.
For third: Northern Districts 172-8 (J Fraser 72) lost to Canterbury 173-6 in 45 overs (H Tiffen 98no) by four wickets.