This article is general information about how US working-time rules interact with a four-day week. It is not legal advice. Employment law varies by state and by role; take advice on your own contracts, payroll and agreements before you pilot.
Most four-day week legal problems are quiet: a docked exempt salary, a non-exempt technician owed overtime for day-off messages, a 4x10 in a daily-overtime state costing more than the pattern it replaced. The researched model — 100-80-100, full pay for 80% of the time — avoids some traps by design and creates others if terms stay unwritten.
The federal baseline: the FLSA
Under the Fair Labor Standards Act, employees are non-exempt or exempt. Non-exempt staff must receive overtime at 1.5 times the regular rate for hours over 40 in a workweek. The FLSA counts the week, not the day: 10 hours on Monday is not federal overtime if the week totals 38. Employers must keep accurate time records for non-exempt staff, and work an employer “suffers or permits” — work you know about and allow, even off the clock — counts as hours worked.
Exempt staff (executive, administrative and professional roles meeting duties and salary-basis tests) are outside federal overtime. Pay is a salary for the job, not an hourly rate. That status is fragile: docking exempt salary for partial-week absences tied to a day-off scheme can risk the exemption.
Reduced 32-hour week. For non-exempt staff, moving from 40 to 32 scheduled hours at the same weekly pay does not itself trigger federal overtime — 32 is below 40. Extra hours still count: 32 scheduled plus 6 on the day off is 38 payable hours; at 41, the hour over 40 is overtime. For exempt staff, keeping salary whole while days fall is the clean approach. Pro-rating salary down turns the pilot into a pay cut and changes the proposition entirely.
Compressed 4x10. Federally this also totals 40, so no federal overtime arises. The trap is state law: states such as California generally require daily overtime after eight hours (subject to alternative-workweek rules), and breaks get harder on 10-hour days. Reduced and compressed are different interventions; do not treat them as interchangeable.
Timekeeping is where reduced weeks get expensive
The highest-risk moment is the day off itself. A non-exempt employee who checks a system or answers a customer on her scheduled day off has worked. If you knew — a log, a manager saw it — “suffer or permit” points one way: pay for it and count it toward 40.
- Define the workweek in payroll: which seven days, and which day is each team’s scheduled day off.
- Keep recording time for non-exempt staff during the pilot. A four-day week is a reason to improve timekeeping, not stop it — you need proof hours really fell.
- Write the off-day rule: no work on the scheduled day off without prior approval; approved hours are recorded and paid. Then enforce it. A rule managers routinely ignore is worse than none.
- Watch exempt staff differently — after-hours activity and workload surveys. Hidden overtime falsifies results and burns people out.
Contracts, leave and benefits checks
- Offer letters and handbooks. If they promise a 40-hour week or daily overtime, amend through written trial terms, not an announcement email.
- PTO in hours, not days, once schedules vary. Decide what happens when a public holiday falls on a scheduled day off, and write the answer down — inconsistency here generates grievances fastest.
- Benefits thresholds. Check hours-based eligibility for health coverage, retirement plans and leave laws so a move to 32 hours moves nobody across a threshold by accident.
- Part-time equity. At 40→32 hours on the same pay, the full-time effective hourly rate rises 25%. Part-timers on the old rate will notice; fair designs uplift part-time hourly rates pro rata.
- Collective agreements. Hours, overtime triggers and scheduling notice may need agreement, not notification.
- Written trial terms: duration, review date, continue/extend/adjust/revert options, and notice if the pattern changes. Bills to lower the federal overtime threshold toward 32 hours have been introduced in Congress in recent sessions, but as of this writing none has become law; do not build contracts assuming one has.
Actionable steps
- Classify the pilot population — every role exempt or non-exempt, flagging borderline roles for legal review.
- Choose reduced or compressed deliberately, and cost any 4x10 pattern under your state’s daily-overtime and break rules before approving it.
- Draft one page of trial terms: workweek, day-off scheduling, timekeeping, off-day rule, holiday treatment, PTO in hours, review date, reversion process.
- Configure payroll before day one; retrofitting pay codes destroys trust.
- Brief managers on “suffer or permit”: if a report works a day off, record it, pay it, stop it recurring — in that order.
- Put the decision date in writing. Staff accept a genuine trial, not an endless experiment.
A four-day week needs ordinary employment law applied carefully, in writing, before the first day off — and that review forces the timekeeping, equity and trial-terms conversations that make pilots succeed.
Sources
- UK 2022 pilot — Autonomy / Cambridge / Boston College, 21 February 2023: https://www.sciencedaily.com/releases/2023/02/230221113132.htm
- US and Ireland pilots 2022 — 4 Day Week Global, December 2022: https://www.internationalworkplace.com/community-zone/news/four-day-week-pioneering-pilot-program-a-huge-success-new-research-reveals
- Iceland trials 2015–2019 — Autonomy / Alda, July 2021: https://phys.org/news/2021-07-shorter-week-boost-productivity-burnout.html
- Atom Bank, 21 December 2022: https://www.personneltoday.com/hr/atom-bank-four-day-week/
Day5Group is a consultancy that assists in the transition to a 4 day work week. More about Day5Group · All blog articles