My problem was worse. I measured at 37.5 so I ordered a 38. I didn't realise that the kilt should be worn tighter than what I measured and that since that is the tightest hole I had no room to tighten it up. I can alter it by moving the straps and buckles around but for now I have just kept it on with a belt and overlapping the aprons more than they are supposed to. For me a 38 heavy weight would probably fit but a standard ('05 standard) is too big.

Depending on how you measured (squeezed the measuring tape a little or kept it just at what your gut sits at) I would go for the smaller one.