Originally Posted by
golfmad
That's against the HMRC rules. You can only claim for costs actually incurred and money actually spent. You won't be able to justify this if there's an audit.
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Southampton HMRC are cool with it - we checked it out a few years ago as we have a number of people who do this. Not even a P11D impact. Not an issue at all so long as true cost is established.
Estimation is accepted practice when done properly. There is even a box you can tick about it on your personal tax return! It's particularly common in expenses and benefits - the whole company cars area is full of estimations, albeit HMRC ones!