England crush New Zealand by 76 runs in Twenty20
Malan was unbeaten on 103 at the close of the England innings with Morgan out in the final over for 91 as England posted an imposing 241 for three and then rolled New Zealand for 165 with 19 balls remaining.
The overwhelming victory set up a winner-takes-all finale in the fifth and final game in Auckland on Sunday.
Malan's 48-ball century was the fastest T20 hundred by an Englishman, his 182-run stand with Morgan is the highest by an England pair and the 241 total is an England record.
Morgan's 21-ball 50 is also an England record. "The message is always the same, play aggressively and back yourself," Malan said.
"It's not very often you have days like that when every time you have a hack at one it lands safe or goes for six. It's as good as it gets."
Between them, the two left-handers hit 13 sixes and 16 fours with Mitchell Santner and Trent Boult the only New Zealand bowlers to escape with a run rate below 10 an over.
New Zealand started their run chase at a fast clip reaching 54 in the fifth over when Martin Guptill was dismissed for 27 and wickets fell regularly after that.
Only Tim Southee (39) and Colin Munro (30) offered any further resistance while Matt Parkinson took four for 47 for England and Chris Jordan finished with two for 24.
Malan is only the second England player to score a T20 century after Alex Hales, who needed 60 balls to reach his hundred.
He advanced from 61 to 89 in a brutal attack in an Ish Sodhi over when he belted three sixes, two fours and a two, and reached his maiden century pulling Boult over the square-leg boundary for another six.
It was a much-need confidence booster for England who won the first match in the series and were then well outplayed in the next two.
After losing the toss, England then lost early wickets with Santner removing Jonny Bairstow for eight and Tom Banton for 31 to have the impressive figures of two for five from his first two overs.
But that changed dramatically as Morgan and Malan took charge and blasted 20 off Santner's next over.
Of the New Zealand bowlers, Blair Tickner finished with none for 50 off his four overs, while Sodhi had none for 49 off three overs and Southee bowled his full complement to finish with one for 47.
48-ball century - Malan’s hundred is fastest by an Englishman
182-run stand - Malan-Morgan partnership is highest by an England pair
241/3 - The total is an England record
21-ball 50 - Morgan becomes the quickest Englishman to this milestone
T Banton lbw Santner 31
J Bairstow c Mitchell b Santner 8
D Malan not out 103
E Morgan c Mitchell b Southee 91
S Billings not out 0
Extras: (lb3, w3, nb2) 8
Total: 241/3 in 20 overs
Fow: 1-16 (Bairstow), 2-58 (Banton), 3-240 (Morgan)
Bowling: Boult 4-0-35-0, Southee 4-0-47-1, Santner 4-0-32-2 (2w, 1nb), Tickner 4-0-50-0 (1nb), Sodhi 3-0-49-0, Mitchell 1-0-25-0 (1w)
New zealand (Toss)
M Guptill c Malan b T Curran 27
C Munro c Brown b Parkinson 30
T Seifert c T Curran b Jordan 3
Grandhomme c Banton b Parkinson 7
R Taylor c Banton b Brown 14
D Mitchell c Jordan b Parkinson 2
M Santner c Billings b S Curran 10
T Southee lbw Parkinson 39
I Sodhi run out (Jordan) 9
T Boult b Jordan 8
B Tickner not out 5
Extras: (lb3, w8) 11
Total: 165/10 in 16.5 overs
Fow: 1-54 (Guptill), 2-59 (Seifert), 3-70 (de Grandhomme), 4-70 (Munro), 5-78 (Mitchell), 6-89 (Taylor), 7-138 (Southee), 8-144 (Santner), 9-154 (Sodhi), 10-165 (Boult)
Bowling: S. Curran 4-0-36-1 (2w), T. Curran 3-0-26-1, Jordan 2.5-0-24-2 (w1), Parkinson 4-0-47-4, Brown 3-0-29-1 (w5).