I searched on HMRC website for references to the "additional costs allowance". The only showings are in the guidance pages relevant to MPs self assessment tax returns. There's no published reference in HMRC manuals.
The Parliament notes on page MPN 2 state that MPs should not include in Box 1 any "benefits and expenses payments received". These should be enter instead in boxes 3 to 9.
The form continues much as you might expect except that it explicitly instructs MPs to exclude any sums received by way of the 'Additional Costs Allowance.'
Now we all know that HMRC guidance is not necessarily the law. So what is the law as regards this allowance? WE can all speculate - and some may well do so.
But I'd love to hear from anyone who currently acts for MPs (or has done in the past).
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