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
- The Department of Labor describes the workweek as a fixed and regularly recurring period of 168 hours (seven consecutive 24-hour periods). It does not have to match the calendar week and can start at any day and hour. (Fact Sheet #23; 29 CFR 778.105)
- Covered, non-exempt employees must receive at least one and one-half times their regular rate for hours worked over 40 in that workweek. Each workweek stands alone: hours are not averaged over two or more weeks. (29 CFR 778.104)
- The pay period (weekly, biweekly, semimonthly, monthly) only decides when you are paid. Under 29 CFR 778.106, overtime is generally due on the regular payday for the period in which the workweek ends. (29 CFR 778.106)
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 starts | Hours per workweek | Overtime hours | Gross for the first four shifts |
|---|---|---|---|
| Sunday 00:00 | 46 (four shifts in one week) | 6 | 46 × $20 + 6 × $10 = $980.00 |
| Wednesday 00:00 | 34.5 and 11.5 (split across two weeks) | 0 | 46 × $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
- Daily overtime. Some states require overtime after a number of hours in a day, not just in a week. California, for example, requires 1.5 times pay after 8 hours in a workday and double time after 12, with additional seventh-day rules (California DLSE). Hitchday does not calculate daily overtime.
- Union contracts and employer policy may pay overtime earlier, pay premiums for certain days, or define the workweek differently.
- Exempt employees (many salaried roles) may not be owed overtime at all.
- Special schedules such as the healthcare 8/80 system and fire-protection work periods have their own rules.
- Rounding and paid breaks change the hours that count.
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.