4×10s vs 5×8s: do they actually pay the same?

Forty hours is forty hours, so under federal rules the two schedules pay exactly the same and the four-day week is a free extra day off. That is the right answer in most of the country. In a handful of states it is wrong — and in California it can be wrong by $6,240 a year, because overtime there is counted per day as well as per week.

The federal answer

Federal overtime is weekly. Anything past 40 hours in a workweek is time and a half, and nothing in the FLSA cares how you arrange those hours across the days. So:

Same money, one more day off, one less commute. That is why compressed weeks are popular and why most people never think about it again. In the great majority of states that instinct is correct.

Where it stops being true

California runs a daily overtime rule alongside the weekly one. Per the state's Division of Labor Standards Enforcement, overtime begins after 8 hours in a workday — time and a half for hours 8 to 12, and double time beyond 12. There is also time and a half for the first 8 hours on a 7th consecutive workday, and double time past 8 on that day.

Apply that to a ten-hour day and each one splits: 8 hours straight, 2 hours at time and a half.

$120 a week, $6,240 a year — eight overtime hours hiding inside a schedule that says 40 on its face. It scales straight with the rate:

After tax, the $30/hr case is about $4,800 a year in the bank — $52,318 against $57,118.

The exception, and how it has to be earned

California does allow a four-day, ten-hour week without daily overtime — but the employer cannot simply decide to run one. California Labor Code §511 requires an alternative workweek schedule approved by "at least two-thirds of affected employees in a readily identifiable work unit" in a secret ballot election.

Where that has been done properly, the statute permits work "for no longer than 10 hours per day within a 40-hour workweek without the payment… of an overtime rate." Beyond the scheduled hours, or beyond 40 in the week, time and a half applies; past 12 hours in a day, or on a day you were not scheduled to work, it is double time.

What to check, wherever you are

• Check whether your state has daily overtime at all. Most do not, and in those states four tens and five eights genuinely are identical. Alaska, Nevada and Colorado are among the states with daily rules of their own — the thresholds differ, so check yours rather than assuming California's numbers apply.
• In California, ask about the ballot. A valid alternative workweek is a documented election, not a policy. Employers must keep records of it.
• Watch the fifth day. On a properly adopted 4×10, a fifth shift that week is overtime from the first hour — and an unscheduled day can reach double time past 8.
• Watch the 12-hour mark. Two hours of overrun on a ten-hour day is ordinary overtime; the thirteenth hour is double time.
• Mind the clock. Under 29 U.S.C. §255(a) a federal claim generally reaches back two years, three if willful. California's own limit for state wage claims is longer — worth asking a local employment lawyer about, since this is a state rule, not a federal one.

The part that has nothing to do with money

Where the pay genuinely is identical, the comparison is about the day, and it is not nothing: a four-day week removes roughly 52 commutes a year. At 45 minutes each way that is about 78 hours of unpaid travel you get back — near enough two working weeks. Set against that, ten-hour days are harder on childcare, and the fatigue on day four is real.

Those are the right things to weigh. Just make sure you are weighing them against the correct paycheque first.

Common questions

Do 4x10s pay more than 5x8s?

Under federal rules, no — both are 40 hours with no overtime, so the pay is identical and the difference is one extra day off. In states with daily overtime the answer can change.

Is a 10-hour day overtime in California?

Hours past 8 in a workday are overtime in California at time and a half, and past 12 at double time — so a ten-hour day is 8 regular plus 2 overtime, unless a valid alternative workweek schedule was adopted under Labor Code §511.

How much could I be owed on a California 4x10 without an alternative workweek?

Eight overtime hours a week. At $30 an hour that is $120 a week, about $6,240 a year — roughly $4,800 after tax. At $45 an hour it is about $9,360 a year.

How is an alternative workweek schedule adopted?

Labor Code §511 requires approval by at least two-thirds of affected employees in a readily identifiable work unit, by secret ballot election. It permits up to 10 hours a day within a 40-hour week without an overtime rate. An employer cannot simply announce one.

What happens if I work a fifth day on a 4x10 schedule?

Those hours are past 40 for the week, so they are overtime from the first hour. On a properly adopted alternative workweek in California, work on a day you were not scheduled can reach double time past 8 hours.

More on shift pay

• My paycheck looks short. How do I check it? — including why daily overtime must be split by actual day, never averaged.
• Is a $3 raise worth 10 more hours a week? — what an extra hour is really worth once you price it.
• All Cimplora pay guides