England take only 12.4 overs to surpass New Zealand's total of 139-8.
England captain Stuart Broad took 3-15 from his four overs to support his decision to bowl first on winning the toss. His bowlers restricted New Zealand to a modest total and the openers were untroubled in chasing down the target.
The match ended a see-sawing series in which England won the first international by 40 runs in Auckland, New Zealand took the second by 55 runs in Hamilton, and England rebounded to win the decider in a cakewalk.
In bowling first, Broad noted that the five previous Twenty20s in Wellington had all been won by the team batting second. The first two matches of the current series had been won by the team batting first but that pattern was broken when New Zealand failed to get on top of an outstanding England attack.
New Zealand made what appeared to be a deliberately cautious beginning, hoping to conserve wickets for an assault on the bowlers in the later overs. But it was never able to break out of that slow beginning and as wickets fell steadily its rate dwindled.
Opener Martin Guptill top-scored with 59 but, batting for his average, took 18.5 overs to achieve that total and his slow scoring helped suffocate the New Zealand innings.
"There was a bit of tennis ball bounce and the pitch was a bit two-paced so it was difficult to score quickly," Guptill said. "And it seemed that every time we started to get something going, we lost a wicket and that stifled our momentum."
Lumb and Hales had no trouble generating momentum on a pitch which provided moderate pace and a generous bounce. Whereas New Zealand had been 20-1 after five overs, England was 57 without loss; after 10 overs New Zealand was 63-2 while England was 93-0.
The England openers then smashed 50 runs from the last 2.4 overs before Lumb completed the victory with a huge six off Ian Butler that pitched on the roof of Westpac Stadium.
Broad conceded 55 runs from four overs in England's defeat in Hamilton - the worst-ever figures by a bowler against New Zealand. He fully atoned on Friday, claiming the wickets of Guptill, his opening partner Hamish Rutherford (11) and Colin Munro (1).
Broad's new ball partner, Steve Finn, conceded only 18 runs from four overs, helping put the brakes on New Zealand's early scoring while Jade Dernbach took 3-36.
Brendon McCullum tried to hit New Zealand out of trouble but he managed only 26 from 20 balls before falling to one of several catches in the deep. The innings contained only three sixes while England's included three times as many.
"I thought the way our bowlers bowled on a good cricket wicket was fantastic," Broad said. "That set the game up.
"Obviously our opening batsmen have come out and really entertained. We're delighted with the hard work we've put in over the past two weeks."
Friday's defeat was a massive setback for New Zealand two days ahead of the first of three one-day internationals.
"England was far too good tonight," McCullum said. "Stuart and his team blew us off the park tonight unfortunately but we'll bounce back strongly in the next series."