The four-day week, the arithmetic of fitting 10-hour shifts into a 24-hour day, and the operations where a 4-10 schedule earns its place.
Schedule GuideA 10-hour schedule usually means four 10-hour days and three days off each week — the 4-10. It gives the same 40 hours as a five-day week with 52 more days off a year, and in our surveys it is the shift length workers pick first. The catch is arithmetic: 10 does not divide into 24. In a 24/7 operation three 10-hour shifts overlap for six hours a day, so 10-hour schedules fit best where the operation runs less than around the clock or where that overlap covers a daily peak.
The basic 10-hour schedule is four workdays of 10 hours followed by three days off. Weekly hours stay at 40. Over a year that is 208 workdays (4 × 52) in place of the 260 a five-day week requires, so each person is at work 52 fewer days for the same hours and the same pay.
What changes is how the days are covered. A four-day work week does not cover a five-day or seven-day operation by itself, and a 10-hour shift does not fit a 24-hour day the way an 8-hour or 12-hour shift does. Most of the design work in a 10-hour schedule is deciding what to do about those two facts.
| 5 days × 8 hours | 4 days × 10 hours | 12-hour, 4 crews (24/7) | |
|---|---|---|---|
| Average hours per week | 40 | 40 | 42 |
| Workdays per year | 260 | 208 | About 182 |
| Days off per year | 105 | 157 | About 183 |
| Shifts needed to cover 24 hours | 3, no overlap | 3, with 6 hours of overlap | 2, no overlap |
| Paid hours to cover one position 24/7 for a week | 168 | 210 | 168 |
Three 8-hour shifts or two 12-hour shifts add up to exactly 24 hours. Ten-hour shifts do not. Two of them cover 20 hours and leave four uncovered. Three of them put 30 staffed hours against a 24-hour day, so two crews are on site together for six hours every day.
For a 24/7 operation that overlap is the whole question. Covering one position around the clock takes 21 shifts a week on 8-hour or 10-hour shifts, but at 10 hours each that is 210 paid hours for 168 hours of coverage — 25% more. At 40 hours a week it takes 5.25 people to fill one position, against 4.2 on 8-hour or 12-hour shifts.
That extra labor is only waste if the overlap has nothing to do. Where workload peaks at the same time every day, the overlap can be placed on the peak and becomes double coverage exactly when it is needed.
There are three common answers, and each one costs something.
Ten-hour schedules tend to fit operations that run 10 or 20 hours a day and not 24, operations with a predictable daily peak that the overlap can cover, and sites where recruiting and retention depend on offering more days off without moving to 12-hour shifts. Distribution centers tied to port and carrier windows are a common example. They are a weaker fit for continuous processes that need the same coverage every hour of the day, where the overlap is paid for and not used.
A pattern or a rule of thumb is only the starting point. The right answer depends on your coverage needs, your workforce’s preferences, your overtime and absence rates, and the policies that go with the schedule — and most sites end up with a design tailored to them. That analysis is what a Shiftwork Solutions engagement does. Talk with us about your operation, or start with the free Shiftwork Assessment.
