26 C.F.R. § 1.162-10

(a) In general. Amounts paid or accrued by a taxpayer on account of injuries received by employees and lump sum amounts paid or accrued as compensation for injuries, are proper deductions as ordinary and necessary expenses. Such deductions are limited to the amount not compensated for by insurance or otherwise. Amounts paid or accrued within the taxable year for dismissal wages, unemployment benefits, guaranteed annual wages, vacations, or a sickness, accident, hospitalization, medical expense, recreational, welfare, or similar benefit plan, are deductible under section 162(a) if they are ordinary and necessary expenses of the trade or business. However, except as provided in paragraph (b) of this section, such amounts shall not be deductible under section 162(a) if, under any circumstances, they may be used to provide benefits under a stock bonus, pension, annuity, profit-sharing, or other deferred compensation plan of the type referred to in section 404(a). In such an event, the extent to which these amounts are deductible from gross income shall be governed by the provisions of section 404 and the regulations issued thereunder.

(b) Certain negotiated plans. (1) Subject to the limitations set forth in subparagraphs (2) and (3) of this paragraph, contributions paid by an employer under a plan under which such contributions are held in a welfare trust for the purpose of paying (either from principal or income or both) for the benefit of employees, their families, and dependents, at least medical or hospital care, and pensions on retirement or death of employees, are deductible when paid as business expenses under section 162(a).

(2) For the purpose of subparagraph (1) of this paragraph, the word “plan” means any plan established prior to January 1, 1954, as a result of an agreement between employee representatives and the Government of the United States, during a period of Government operation, under seizure powers, of a major part of the productive facilities of the industry in which the employer claiming the deduction is engaged. The phrase “plan established prior to January 1, 1954, as a result of an agreement” is intended primarily to cover a trust established under the terms of such an agreement. It also includes a trust established under a plan of an employer, or group of employers, who, by reason of producing the same commodity, are in competition with the employers whose facilities were seized and who would therefore be expected to establish such a trust as a reasonable measure to maintain a sound position in the labor market producing the commodity. For example, if a trust was established under such an agreement in the bituminous coal industry, a similar trust established in the anthracite coal industry within a reasonable time, but before January 1, 1954, would qualify under subparagraph (1) of this paragraph.

(3) If any trust described in subparagraph (2) of this paragraph becomes qualified for exemption from tax under the provisions of section 501(a), the deductibility of contributions by an employer to such trust on or after any date of such qualification shall no longer be governed by the provisions of section 162, even though the trust may later lose its exemption from tax under section 501(a).

(c) Other plans providing deferred compensation. For rules relating to the deduction of amounts paid to or under a stock bonus, pension, annuity, or profit-sharing plan or amounts paid or accrued under any other plan deferring the receipt of compensation, see section 404 and the regulations thereunder.