SHIFT PAY GUIDE
How Overtime Works on 12-Hour Shifts (Weekly vs Daily Rules)
Twelve-hour shifts make overtime confusing on purpose of the calendar: three shifts one week (36 hours), four the next (48). When does time-and-a-half actually start? The answer depends on federal weekly rules, your state's daily rules, and — if you're on a hospital schedule — possibly an 8/80 agreement.
The federal rule: 40 hours per workweek
The FLSA sets one trigger: more than 40 hours in a defined workweek pays at least 1.5× your regular rate. A 36-hour week of three twelves earns zero OT. A 48-hour week of four twelves earns 8 hours of it.
Your workweek is a fixed 7-day cycle your employer defines — it doesn't have to be Sunday–Saturday, and it doesn't reset because a pay period ends. If your employer's week starts Sunday and your shifts straddle it, the hours count in the week they're actually worked. Overnight shifts split at the week boundary.
State daily-overtime rules
A handful of states add daily triggers. California is the big one: over 8 hours in a day pays 1.5×, and over 12 hours pays 2×. Alaska, Nevada, and Colorado have daily rules too (with variations and exemptions).
On a California 12-hour schedule, every shift already includes 4 daily-OT hours — before the weekly count even matters. If you work twelves in a daily-OT state, your paycheck math is genuinely different; check your state's rules.
Hospitals: the 8/80 exception
Hospitals and residential-care facilities may adopt the FLSA's 8/80 system instead: overtime after 8 hours in a day OR 80 hours in a 14-day period, whichever benefits the employee more. Under 8/80, every 12-hour shift includes 4 OT hours — which is why many hospitals schedule nurses in 36-hour weeks on straight time with built-in incentives instead.
The part everyone gets wrong: your OT rate
Overtime is 1.5× your regular rate — which includes shift differentials, not just base pay. A night nurse at $38.50 base with a $4 night differential has an effective rate of $42.50 in the window; OT hours on those nights pay $63.75, not $57.75.
ShiftCheck applies weekly OT chronologically at your real effective rate, hour by hour, across week boundaries. Paint your month and the OT hours light up with a ⚡ — no spreadsheet.
Do the math for your numbers: Overtime pay calculator →
FAQ
Do I get overtime for a single 12-hour shift?
Under federal rules, no — OT starts past 40 hours in the workweek. In daily-OT states like California, yes: hours 9–12 pay 1.5×. Under a hospital 8/80 plan, hours 9–12 also pay OT.
Is working 3 twelves considered full time?
Almost universally yes — 36 hours is treated as full-time in healthcare and most 24/7 operations, with full benefits.
Can my employer average my 36- and 48-hour weeks to avoid OT?
No. Each workweek stands alone under the FLSA (outside a lawful 8/80 hospital plan). A 48-hour week owes 8 OT hours even if the next week is 36.
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