The Freelance Thread (Contractor, IR35)

depends whether she's doing any work for the salary
if you're paying her a salary because it's more efficient to pay the extra to her than it is you (if, say, it keeps you both the lower bracket rather than you tripping into a higher one) then it's still avoidance
but as you say, you wouldn't be the first or last if you did it that way

I'd not heard of money boxing. When I contracted then I paid myself dividends to cover what I needed for mortgage, bills etc and left the rest in the company. I'd guess as I only contracted for a few years then whatever was in the company wasn't large enough that HMRC would have thought of it as excessive. I did then close the company via MVL process when I took a permanent job (so no issues of starting up another company shortly after etc).

But when you say

How can HMRC claim this is avoidance as any money/profits remaining in the company (at each year end) would be subject to corporation tax etc, and therefore any tax due would already have been paid. Hardly avoidance is it?

If you had enough money in your personal accounts that you could afford to just pay yourself the tax free allowance and left everything else in the company for a long time - no dividends etc.
And then you MVL'd the company and paid 10% on essentially everything that was left then that would be avoidance as you'd be manufacturing a situation where you'd pay less tax than would be expected.
your company isn't avoiding paying tax, but you might be

There's a difference between evasion and avoidance. If you took cash in hand for the work and didn't declare it then it's evasion. Avoidance, I believe, is more open to interpretation. The spirit of the rules as it were