You Do Need power plug adapter while traveling from Saint Vincent and the Grenadines to Montserrat.

Here is Why You Need An Adapter

The outlet and plug type used in Montserrat are A and B and in Saint Vincent and the Grenadines are A, B and G. This is how they look like.

Saint Vincent and the Grenadines

In Saint Vincent and the Grenadines, outlets of type A, B and G are in use.

Type A

Type B

Type G

Montserrat

In Montserrat, outlets of type A and B are in use.

Type A

Type B