Williamson (112 off 88 balls) and Taylor (102no off 70 balls) dismantled the tourists’ attack and posted a massive score of 369-5 from their 50 overs.
It continues a remarkable run of form for the pair ??? it was Williamson???s third ODI hundred and 12th score of fifty plus in 18 innings and Taylor???s fourth century since the beginning of last year.
Mohammad Hafeez (86) formed part of a 111-run opening stand with Ahmed Shehzad (55) in reply but once the first wicket fell,??Pakistan quickly crumbled to a heavy defeat.
Black Caps captain, Brendon McCullum, moved quickly to 31 off only 27 balls but was then bowled by veteran all-rounder Shahid Afridi.
But that only brought Williamson to the crease, and he put on a 128-run partnership with Martin Guptill (76).
Guptill fell in the 28th over to the part-time leg-spin of Shehzad but Taylor continued to pile the pressure of the visiting bowlers alongside new partner Williamson ??? taking a particular liking to Bilawal Bhatti, whose 10 overs went for 93 runs.
Williamson eventually fell to the pick of the Pakistan bowlers, Mohammad Irfan (2-52), with 66 balls left in the innings but Taylor and Grant Elliott (28 off 21) then struck big sixes to help add 119 runs came from the final 11 overs.
Pakistan started well in reply with Hafeez and Shehzad countering the New Zealand pacemen ??? particularly Tim Southee ??? early on in the innings.
The spin of Nathan McCullum then accounted for Shehzad and regular wickets fell throughout the rest of their innings ??? captain Misbah-ul-Haq (45) the only other batsman to pass 13 runs.
Black Caps paceman Adam Milne (2-52) was particularly impressive as wickets were shared around between Southee (2-52), McCullum (2-33) and Elliott (2-35).
Defeat condemmed Pakistan to their fourth straight series defeat while New Zealand eased to their third-straight win ??? and eighth in their last 10 ODIs ??? ahead of the World Cup which starts in under two weeks’ time.