TOP

  S   M   L
PTP
16" 17" 18"
Waist 14" 15" 16"
Length 16" 16.5" 17"

*Model is 1.64m, UK 6 and wears size S

If you are in between sizes for PTP/waist, it is best recommended to size up. 

*In between sizes refers to your measurements falling between 2 sizes, example size S & M.

BOTTOM

   S   M   L
Waist 13" 14" 15"
Hip 20" 21" 22"
Rise 13.5" 14" 14.5"
Length 15" 15.5" 16"

*Model is 1.64m, UK 6 and wears size S

There's allowance at the waist/hip. You may stick to your usual size for a relaxed fit or size down for a slimmer fit.