26 CFR 31.3306(b)(7)-1: (b)(7)-1 Payments other than in cash for service not in the course of employer's trade or business.

The term “wages” does not include remuneration paid in any medium other than cash for service not in the course of the employer's trade or business. Cash remuneration includes checks and other monetary media of exchange. Remuneration paid in any medium other than cash, such as lodging, food, or other goods or commodities, for service not in the course of the employer's trade or business does not constitute wages. Remuneration paid in any medium other than cash for other types of services does not come within this exclusion from wages. For provisions relating to the circumstances under which service not in the course of the employer's trade or business does not constitute employment, see § 31.3306(c)(3)-1.