You Do Need power plug adapter while traveling from São Tomé and Príncipe 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 São Tomé and Príncipe are C and F. This is how they look like.

In São Tomé and Príncipe, outlets of type C and F are in use.

Type C

Type F

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

Type G

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