Natalie Sciver hit a brilliant 58* as England chased down 156 to beat West Indies by five wickets and win the ODI series 3-2.
Player of the match Alex Hartley took 4-24, including the wicket of West Indies captain and dangerwoman Stafanie Taylor, as England restricted the hosts to 155 in a disciplined fielding display.
Pace bowler Katherine Brunt was also on form with the ball, getting England's breakthrough with the wicket of opener Shaquana Quintyne and finishing on figures of 3-35 for the innings.
Gergia Elwiss then removed Hayley Matthews for 22 before Hartley and fellow spinner Laura Marsh piled the pressure on the middle order.
Hartley – on her first overseas tour – dismissed Deandra Dottin, Merissa Aguilleira and Shemaine Campbelle before taking the prized wicket of Taylor, who was looking good on 57.
The left-arm spinner's overall total of 13 wickets was the highest by any England Women's player in a bilateral ODI series.
Brunt and Heather Knight took care of the tail end to bowl out the home side and set up a manageable run-chase.
England openers Lauren Winfield and Tammy Beaumont started positively before going for 12 and 24 respectively and Sciver's arrival injected the necessary energy into proceedings as she notched up her sixth ODI half-century.
Amy Jones helped England finish with a flourish, hitting one over the top for four to seal the win and the series.
England captain Knight was delighted with the team's dominant display.
Speaking immediately after the win, she said: “I’m really happy with how we have stood up and delivered a strong, winning performance in the final match of the series today. To come to the Caribbean and beat the ICC Women’s World T20 champions on their home patch, in tough conditions, and with a couple of set-backs along the way, shows how much character, desire and talent there is within this squad.
“Throughout the five matches, momentum has constantly shifted between the two sides, which shows how evenly matched the teams are.
“It is a brilliant feeling to win the series decider, and I know that we will all take a lot of belief and confidence from this experience. We are learning and growing as a squad all the time, and we are already looking forward to the next challenge of taking on Sri Lanka in Colombo next month.