Sarfraz Ahmed and Shoaib Malik shared a 163-run partnership to give Pakistan a four-wicket victory in the fifth and final ODI on Sunday and deny England a series sweep.
Ahmed scored 90 off 73 balls and Malik finally came good in the series with 77 off 80 deliveries to carry Pakistan to 304-6 in 48.2 overs.
Mark Wood's twin strike in one over had pegged back Pakistan to 77-3 before Ahmed and Malik's fourth-wicket partnership. Earlier, England's 302-9 revolved around opening batsman Jason Roy's 87 and allrounder Ben Stokes' 75 after Pakistan won the toss and opted to field.
Earlier, Jason Roy and Ben Stokes both struck quickfire fifties as England made 302 for nine in the fifth and final one-day international against Pakistan in Cardiff on Sunday.
Roy made 87 and Stokes an ODI-best 75 as England, bidding for a first 5-0 clean sweep of a home one-day series, set Pakistan a challenging total to chase.
At 244 for five England — who posted a world record 444 for three in the third ODI in Nottingham — were set for another huge score. But Pakistan pegged them back with paceman Hasan Ali taking an ODI best four for 60 and left-arm quick Mohammad Amir three for 50.
Opening batsman Roy, dropped on 56 when a diving Rizwan could not hold a tough chance at mid-wicket, put on 72 for the fourth wicket with Stokes. All-rounder Stokes and wicket-keeper Jonny Bairstow then added 55 for the fifth wicket.
England made a rapid start after being sent into bat on a green-tinged pitch and under overcast skies by Azhar Ali, who clearly hoped his pace bowlers could exploit the helpful conditions.