Andre Fletcher top-scored with 42 from 44 balls, all-rounder Dalton Polius struck 37 and captain Liam Sebastien gathered 33, but the Windwards found it difficult to recover after slumping to 29 for three after six overs.
Earlier, captain Kirk Edwards stroked 64 from 93 balls and Dwayne Smith weighed in with an attacking 29-ball, unbeaten 52 to propel Barbados up to 279 for seven after they won the toss and chose to bat.
Opener Kraigg Brathwaite hit a patient 44 from 76 balls while in contrast Kenroy Williams smashed 36 from 24 deliveries and wicketkeeper Shane Dowrich, 33 from 37 balls, in breezy knocks that gave the Barbados innings impetus.
Fast bowler Nelon Pascal finished with three for 87 while left-arm speedster Delorn Johnson picked up two for 57.
The hosts lost Rashidi Boucher for 18 with the score on 28 in the seventh over but flourished through an 88-run, second-wicket stand between Edwards and Brathwaite.
Edwards struck four fours and a six while Brathwaite counted just two fours in his innings.
When Barbados lost their way slightly to slip to 200 for six in the 44th over, Smith and Williams combined in a rollicking seventh-wicket partnership of 77 off just 36 deliveries, to rally the innings.
Smith blasted three fours and four sixes while Williams pounded five boundaries.
In reply, the Windwards were in early trouble after Holder knocked over the dangerous Devon Smith for 13 and Keddy Lesporis for one, as the visitors lost three quick wickets.
Fletcher and Miles Bascombe (23) put on 55 for the third wicket to restore sanity to the Windwards run chase but once both batsmen fell in successive overs to leave the score on 84 for five in the 18th over, victory seemed out of the question.
Polius and Sebastien staged a rearguard action with a 69-run, sixth-wicket stand to make them believe again before Carter engineered a collapse which saw the last five wickets fall for 27 runs.
BARBADOS innings
K. Brathwaite c & b Bobb 44
R. Boucher c wkp. Charles b Pascal 18
K. Edwards c Polius b Pascal 64
S. Dowrich c Fletcher b Johnson 33
D. Smith not out 53
J. Carter c Polius b Johnson 13
K. Mayers b Pascal 10
K. Williams run-out 36
A. Nurse not out 0
Extras: (w-5, nb-3) 8
Total: (7 wkts, 50 overs) 279
Fall of wickets: 1-28, 2-116, 3-150, 4-165, 5-187, 6-200, 7-277.
Bowling: Pascal 10-1-87-3 (w-5, nb-2), Johnson 10-1-57-2 (nb-1), Sebastien 10-0-36-0, Bobb 10-0-37-1, Polius 4-0-21-0, Mathurin 6-0-41-0.
WINDWARDS innings
J. Charles c Smith b F. Edwards 0
D. Smith c Carter b Holder 13
A. Fletcher c Smith b Williams 42
K. Lesporis c Nurse b Holder 1
M. Bascombe lbw b Nurse 23
L. Sebastien c Nurse b Carter 33
D. Polius b Carter 37
A. Bobb c Mayers b Carter 7
D. Johnson c K. Edwards b Carter 10
N. Pascal b Carter 0
G. Mathurin not out 3
Extras: (b-1, w-8, nb-2) 11
Total: (all out, 47 overs) 180
Fall of wickets: 1-8, 2-23, 3-29, 4-84, 5-84, 6-153, 7-161, 8-177, 9-177.
Bowling: F. Edwards 7-1-31-1 (w-5, nb-1), Holder 10-0-38-2, Carter 10-0-26-5 (w-3, nb-1), Mayers 1-0-10-0, Nurse 9-1-34-0, Williams 10-1-40-1.
Points: Barbados 5, Windward Islands 0.