http://www.legislation.gov.uk/ukpga/2005/5/section/34/notesIncome taxTaxLegal servicesLegislationIncomeExplanatory Notes to Income Tax (Trading and Other Income) Act 2005Inland RevenueKing's Printer of Acts of Parliament2020-04-20 5 24 March 2005 158 This section contains rules for the deduction of expenses and losses in calculating the profits of a trade. It is based on section 74(1)(a) (expenses) and (e) (losses) of ICTA. 159 Section 74(1)(a) of ICTA provides that in calculating the profits of a trade no deduction is allowed for expenditure which is not incurred “wholly and exclusively” for the purposes of that trade. This could be construed to mean that if expenditure is incurred partly for trade purposes and partly for some other purposes, no part of that expenditure can be deducted in arriving at the trade profits. 160 But section 74(1)(c) of ICTA, which prohibits any deduction in respect of the rent of premises used for residential or “domestic” purposes, provides for the apportionment of rent paid for premises used partly as residential accommodation and partly for the purposes of a trade. And in practice, a deduction is allowed for any expenditure which can be apportioned between trade and non-trade expenditure – for example, expenditure on a car used partly for trade and partly for private purposes. 161 There is judicial support for allowing a deduction where expenditure incurred for more than one purpose can reasonably be apportioned between expenditure incurred for the purpose of the trade and non-trade expenditure. See, for example, Lochgelly Iron and Coal Company Ltd v Crawford (1913), 6 TC 267 CS, in which a deduction was allowed for part of a subscription to a trade association and Copeman v Flood (1941), 24 TC 53 KB, in which the High Court remitted the case to the Commissioners to find as a fact whether the remuneration paid to certain directors who were also shareholders in the family company was wholly and exclusively expended for the purpose of the Company's trade, and if not, how much of the remuneration was so expended. 162 Conversely, the courts have held that if it is not possible to identify any part of the expenditure which is incurred wholly and exclusively for the purposes of the trade, no apportionment is possible. See, for example, Mallalieu v Drummond (1983), 57 TC 330 HL in which no deduction was allowable for professional clothing worn for warmth and decency as well as being required by the taxpayer’s profession. 163 So subsection (2) of this section provides for the deduction of any part or proportion of expenses incurred partly for the purposes of the trade and partly for some other purpose which can be identified as incurred wholly and exclusively for the purposes of the trade. And because rent on dual purpose accommodation can be apportioned under subsection (2) of this section, it is not necessary to rewrite section 74(1)(c) of ICTA. 2 STC [1983] 665