North Harbour were able to exert pressure on the Makos in the first spell with some pressing defence, but they still missed more tackles than they would have liked and the Makos had more ball. They muscled up with some bruising defence in the second half but Harbour retained possession well.
Earlier, Makos second five David Havili scored the first try after a powerful burst by wing James Lowe and a silky touch by hooker Andrew Makalio, who later scored from a clinical lineout drive.
Harbour's riposte was swift, fullback Matt McGahan the finisher and wing Tevita Li the creator with a devastating break on the counter.
The trusty boots of Bryn Gatland and Banks did the rest, both racking up 12 points each.
North Harbour 27 (Matt McGahan, Matt Vaega, Adrian Smith tries; Bryn Gatland 3 con, 2 pen)
Tasman 27 (David Havili, Andrew Makalio, Shannon Frizell tries; Marty Banks 3 con, 2 pen)
HT: 13-13