England were bowled out for 132 in the decider and while West Indies never got into their rhythm, Hope held their reply together and then won the game with a powerful six over extra-cover off the second ball of the final over.
The win is the third straight T20 international series win for West Indies in 2023 as they prepare to host the World Cup for the shortest format in June.
It was a disappointing end to the mini-tour for Jos Buttler's England side, who had also lost the 50-over series in the Caribbean 2-1.
The surface at the Brian Lara Academy offered help to the spinners and slow left-armer Gudakesh Motie took full advantage, picking up three wickets for 24 runs in his four overs.
West Indies' other left-arm orthodox spinner, Akeal Hosein, chipped in with two for 20 in his four overs as the home side restricted England to the lowest target set in the series.
England skipper Jos Buttler was removed for 11 when he stepped outside the off-stump and tried to turn seamer Jason Holder down the leg-side but was caught by Oshane Thomas.
Hosein then bowled Jacks before a beautiful delivery before Motie got significant turn as he claimed the prize wicket of Phil Salt (38).
Salt had scored rapid centuries in both the last two games, won by England as they fought back to level the series at 2-2.
Liam Livingston threatened with a swift 28 before he was caught and bowled by Motie and Moeen Ali was also aggressive before he was caught by a teamwork catch with Andre Russell throwing the ball to skipper Rovman Powell as he headed towards the boundary rope.
England were bowled out with three balls remaining of their 20 overs when Sam Curran was caught by Sherfane Rutherford off Holder.
The home side's reply got off to a flying start with 20 off the first two overs before Brandon King was removed by Topley and when Woakes bowled Nichola Pooran there was hope for England.
But Sherfane Rutherford (30) put on a 41 run partnership with Hope that stabilised the innings only for England to apply some late pressure.
Sam Curran bowled the penultimate over, removing Andre Russell and conceding just two runs to leave West Indies needing nine off the final over.
An inside edge from Holder allowed West Indies to scamper three before Woakes went full and wide to Hope who smashed the ball over the rope to the delight of the home crowd.
