How US Federal Pay Periods Work
26 biweekly pay periods per year, anchored to the OPM-published schedule. How payday is computed and what happens at year-end.
The 14-day cycle
A US federal pay period is exactly 14 days long and starts on a Sunday. The Office of Personnel Management publishes the start, end, and payday for every pay period for the upcoming leave year.
Most agencies pay on the second Friday after each pay period closes — exactly 10 calendar days after the period end date. If that Friday lands on a federal holiday, payment shifts to the preceding business day.
26 versus 27 pay-period years
26 × 14 = 364 days, leaving roughly one day of calendar drift per year (two days in leap years). Every 11 years or so the calendar drift produces a 27-period year. The most recent 27-period leave year was 2024 for some pay calendars and 2025 for others, depending on the agency's payroll provider.
Agencies handle 27-period years differently: some prorate annual salary across 27 paychecks (each paycheck slightly smaller), some pay the full annual salary across 26 and treat the 27th as a one-time supplement. Federal contractors mirroring the federal calendar should confirm with payroll providers which convention applies.
Leave accrual
Federal annual leave accrual is computed per pay period, not per calendar month. Employees with under three years of service accrue 4 hours per pay period; three to fifteen years, 6 hours; over fifteen years, 8 hours (plus a final 4-hour bump in the last pay period of the leave year for the over-three-year tiers).
How payday is computed
Each US federal pay period is 14 days, starts on Sunday, ends on the second Saturday, and pays on the second Friday after the period closes — exactly 10 calendar days after period end. That puts payday on a Friday for every pay period. If the standard payday lands on a federal holiday, payment shifts to the preceding business day; this is why some Decembers and Januarys see the year's pay periods pushed forward by one day.
OPM publishes the canonical pay period calendar annually. FiscalGrid mirrors the OPM-published schedule for 2023–2027 with start, end, and payday for every pay period; non-federal employers using a federal-style biweekly cadence can use the same dates as a reference.
Pay periods at year-end
A standard year contains 26 pay periods, but every 11–12 years a 27th pay period falls in the federal fiscal year because the biweekly cadence drifts against the 365-day calendar. This is a payroll-system event with material implications: budgets built on 26 pay periods underfund payroll by ~3.8% in a 27-pay-period year. Federal HR systems handle this automatically; smaller employers using a federal-style cadence sometimes do not, and the variance shows up as an unexplained Q4 payroll overrun.