29 C.F.R. § 531.58 Initial and terminal months.
Title 29 - Labor
An exception to the requirement that an employee, whether full-time, part-time, permanent or temporary, will qualify as a tipped employee only if he customarily and regularly receives more than $20 a month in tips is made in the case of initial and terminal months of employment. In such months the purpose of the provision for tipped employees would seem fulfilled if qualification as a tipped employee is based on his receipt of tips in the particular week or weeks of such month at a rate in excess of $20 a month, where the employee has worked less than a month because he started or terminated employment during the month.
Title 29: Labor
PART 531—WAGE PAYMENTS UNDER THE FAIR LABOR STANDARDS ACT OF 1938
Subpart C—Interpretations
Payment of Wages to Tipped Employees
§ 531.58 Initial and terminal months.