Pakistan put up 340/7 riding Babaz Azam's 115 and half century by Mohammad Hafeez. However, their bowlers failed to defend the total even after reducing England to 216/5 at one stage, when Joe Root, Jos Buttler and Moeen Ali were dismissed in quick succession, a collapse of 4 for 15.
It was Ben Stokes who then scored an unbeaten 71 off 64 balls to guide England home as Pakistan bowlers suddenly lost the plot.
In the third rubber too, Pakistan had failed to defend 359.
England have an insurmountable 3-0 series lead. The final ODI takes place in Leeds on Sunday.
