You Do Need power plug adapter while traveling from Costa Rica to United Kingdom (UK).

Here is Why You Need An Adapter

The outlet and plug type used in United Kingdom (UK) is G and in Costa Rica are A and B. This is how they look like.

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

Type A

Type B

In United Kingdom (UK), outlets of type G are in use.

Type G

I am from

going to