Andrew Flintoff grabbed a hat-trick as West Indies, chasing 173 to win, were bowled out for 146 with an over to spare in a game reduced to 29 overs a side after rain had delayed the start at the Beausejour stadium.
It was England´s first limited overs series win in the Caribbean.
"It´s been a long, hard tour and it´s very special to come out of it with a win. We´ve worked very hard," said England captain Andrew Strauss whose side lost the Test series.
West Indies skipper Chris Gayle said: "It´s unfortunate we lost but I have to have give England credit. It was a good wicket to bat on but they bowled well."
Brief scores:
England 172-5 off 29 overs (Kevin Pietersen 48, Ravi Bopara 44, Paul Collingwood 35 not out, Matt Prior 25 not out; Sulieman Benn 2-23, Kieron Pollard 2-31)
West Indies 146 all out off 28 overs (Dwayne Bravo 33, Kieron Pollard 30, Ramnaresh Sarwan 23; Andrew Flintoff 5-19, James Anderson 2-34)
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