Bairstow scored back-to-back tons, his whirlwind century on Saturday inspiring England to a crushing seven-wicket victory in the fifth and final ODI against the Black Caps.
Bairstow's 104 off 60 deliveries, backed by 61 from fellow opener Alex Hales transformed the winner-takes-all showdown from an expected tight contest into a one-way event.
In 16 matches together since 2014 they have scored 1000 plus runs with five half-centuries and three century stands only eclipsed by India's Shikhar Dhawan-Virat Kohli and England's Jason Roy-Joe Root.
The absence of Ross Taylor, who aggravated his quadriceps injury during his match-winning, unbeaten 180 in the fourth ODI, took the punch out of their middle order. Chris Woakes and Adil Rashid picked up three wickets apiece.
Root (23) and Ben Stokes (26) eased England home with 27 runs off the next 36 balls to complete the most comfortable of victories.
Hales anchored the other end, compiling 61 off 74 balls as the pair milked the bowling and capitalised on a New Zealand side failing to ignite.
There was little doubt about England's prowess on true batting pitches, but questions remained how willing they were to curb their natural instincts with the Champions Trophy semi-final against Pakistan and two startling collapses against the swinging ball, at Lord's and in Adelaide, as examples.
Munro will continue prioritising playing for New Zealand and Auckland in the Twenty20 and 50-over formats, but will not play four-day cricket or in the upcoming New Zealand XI warm-ups against England.
"We were disappointed with how we did in the last game when we could have potentially won the series - because we got ourselves into a position [to do that]".
England now travel to Hamilton for a tour match beginning on 13 March, before the two-match Test series starts on 22 March.
Once opener Martin Guptill fell for 47, New Zealand looked close to subsiding.
They timed their partnership well, first being cautious against Moeen and Rashid to make their way to half-centuries, before accelerating.
Once New Zealand slumped to 93-6, only one result appeared possible. Earlier he inspired in the field with a one-handed catch of Tim Southee running around the deep mid-wicket boundary.
It needed three from the last over: the first two balls bowled by Tom Curran yielded no run, but Nicholls hit the third for six into the midst of an excited crowd to end the game. It was clean hitting.
New Zealand captain Kane Williamson: "We lacked discipline with the bat".
Not for the first time, it was the bowlers who put England in contention, restricting New Zealand to 223 all out.
England's domination began at the start of the day when Morgan won the toss and elected to bowl. "I think [it was great] the way the guys went out in a game that people had compared to a knockout in the World Cup next year and said "Right, this is how we'll react".