29 C.F.R. § 4.167
The wage payment requirements under the Act for monetary wages specified under its provisions will be satisfied by the timely payment of such wages to the employee either in cash or negotiable instrument payable at par. Such payment must be made finally and unconditionally and "free and clear." Scrip, tokens, credit cards, "dope checks", coupons, salvage material, and similar devices which permit the employer to retain and prevent the employee from acquiring control of money due for the work until some time after the pay day for the period in which it was earned, are not proper mediums of payment under the Act. If, as is permissible, they are used as a convenient device for measuring earnings or allowable deductions during a single pay period, the employee cannot be charged with the loss or destruction of any of them and the employer may not, because the employee has not actually redeemed them, credit itself with any which remain outstanding on the pay day in determining whether it has met the requirements of the Act. The employer may not include the cost of fringe benefits or equivalents furnished as required under section 2(a)(2) of the Act, as a credit toward the monetary wages it is required to pay under section 2(a)(1) or 2(b) of the Act (see § 4.170 ). However, the employer may generally include, as a part of the applicable minimum wage which it is required to pay under the Act, the reasonable cost or fair value, as determined by the Administrator, of furnishing an employee with "board, lodging, or other facilities," as defined in part 531 of this title, in situations where such facilities are customarily furnished to employees, for the convenience of the employees, not primarily for the benefit of the employer, and the employees' acceptance of them is voluntary and uncoerced. (See also § 4.163(k) .) The determination of reasonable cost or fair value will be in accordance with the Administrator's regulations under the Fair Labor Standards Act, contained in such part 531 of this title. While employment on contracts subject to the Act would not ordinarily involve situations in which service employees would receive tips from third persons, the treatment of tips for wage purposes in the situations where this may occur should be understood. For purposes of this Act, tips may generally be included in wages in accordance with the regulations under the Fair Labor Standards Act, contained in part 531. (See also § 4.6(q) and § 4.163(k) .) The general rule under that Act provides, when determining the wage an employer is required to pay a tipped employee, the maximum allowable hourly tip credit is limited to the difference between $2.13 and the applicable minimum wage specified in section 6(a)(1) of that Act. (See§ 4.163(k) for exceptions in section 4(c) situations.) In no event shall the sum credited as tips exceed the value of tips actually received by the employee. The tip credit is not available to an employer unless the employer has informed the employee of the tip credit provisions and all tips received by the employee have been retained by the employee (other than as part of a valid tip pooling arrangement among employees who customarily and regularly receive tips; see section 3(m) of the Fair Labor Standards Act).
29 C.F.R. §4.167