Overtime: workweek versus pay period

If you work a rotating schedule, the most common source of surprise on a pay stub is that overtime is not calculated on the pay period. This guide explains the federal rule, shows it with 12-hour shifts, and lists where your own rules may differ. It describes U.S. federal law (the Fair Labor Standards Act, FLSA) in general terms. It is not legal advice.

The federal rule in three sentences

Example 1: the same shifts, two different workweeks

A 4-on/4-off worker works 12-hour shifts with a 30-minute unpaid break (11.5 paid hours), at $20 an hour. Shifts fall on Sunday to Wednesday, then Monday to Thursday the following week, and so on.

Employer's workweek startsHours per workweekOvertime hoursGross for the first four shifts
Sunday 00:0046 (four shifts in one week)646 × $20 + 6 × $10 = $980.00
Wednesday 00:0034.5 and 11.5 (split across two weeks)046 × $20 = $920.00

Identical work, $60 apart, purely because of where the workweek starts. Employers may choose the starting point but generally cannot change it just to avoid overtime (29 CFR 778.105). Find out yours; it is often in the handbook or on the pay stub's week-ending date.

Example 2: a workweek split by a paycheck

Same worker, a four-shift run from Tuesday to Friday, Sunday workweek, paid semimonthly (1st–15th and 16th–end of month). In the week of Sunday January 11, shifts fall on Tuesday the 13th, Wednesday the 14th, Thursday the 15th and Friday the 16th: 46 hours in one workweek, 6 of them overtime. The 40-hour mark is crossed during the Friday shift, so the Hitchday pay calculator shows the Friday shift as 5.5 regular and 6 overtime hours, all in the second pay period, while the first period holds 34.5 regular hours from that week. Pay period one does not "reset" and does not show overtime for that week; the overtime lands on the 16th. Payroll systems differ in how they time the overtime payment for a straddling week (see 778.106 above), so treat the allocation as an estimate and compare with your employer's rule.

Example 3: night differentials count toward the regular rate

If you earn a night differential, the Department of Labor's regulations treat it as part of your regular rate (29 CFR 778.207(b)). The regular rate is the week's total straight-time pay divided by the hours actually worked in the week (29 CFR 778.109), and the overtime premium is half of that rate for each overtime hour (when overtime is time and a half).

Worked example: two day shifts and two night shifts, 46 hours, $20 an hour plus $2 per night hour. Night hours = 23. Straight-time pay = 46 × $20 + 23 × $2 = $966. Regular rate = $966 / 46 = $21.00. Overtime premium = 0.5 × $21 × 6 = $63. Gross = $1,029.00. Some employers instead pay each overtime hour at 1.5 times that hour's own rate; here that gives $1,032.00 because the overtime hours were all night hours. The calculator lets you pick either method so you can match your pay stub.

Where the rules differ for you

When in doubt, ask your payroll department for the workweek definition, how overtime is calculated with differentials, and which paycheck a split week lands on. For a wage dispute, contact the U.S. Department of Labor Wage and Hour Division or your state labor agency.

Try it with your schedule