Michael P. Thompson wrote:

When they assign sizes to wading
boots, do they compensate for the thickness of the waders you wear under
them, or do the sizes correspond to your regular shoe size?

In my experience, they don't compensate for the thickness of the waders.
That makes sense. If you're wearing neoprene-foot waders you'll need a
larger size than if you're wearing stocking-foot waders.

I may have to
order some online, but I'm not sure how to make reasonably certain I get the
right size.

JR had it right. Don't buy boots online. Take your waders into a store
and try on the boots. Most shops have neoprene booties you can use to
get a fit, but your own waders would be better.

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