BIM46405 | Specific deductions: professional fees: general principles
From HM Revenue & Customs · Business Income Manual
Professional fees are not allowable if they are:
capital (see BIM35000 onwards), or
Except where the matter is clear-cut, the circumstances surrounding the payment and the precise nature of the professional services provided need to be examined to consider the nature and underlying purpose of the expenditure when it is incurred. It is immaterial that the expenditure may subsequently prove to be abortive, see Pyrah v Annis and Co Ltd [1956] 37 TC 163 and ECC Quarries v Watkis [1975] 51 TC 153. The latter case is discussed in BIM35325.