Why it happens
How the calendar creates a 27th pay period
A biweekly pay cycle delivers a paycheck every 14 days. In a standard year with 365 days, that produces 26 complete periods (364 days) plus one leftover day. Over time, that extra day shifts each year's first pay date forward by one day of the week. After about 11 years, the shift is large enough that a 27th pay date falls within the calendar year.
Whether a specific year has 27 periods depends on which day of the week your company's biweekly cycle starts. Two companies with different pay-date schedules may experience 27-period years in different calendar years. This is why there is no single universal list of "27-period years" — it varies by employer.
How employers handle the 27th period for salaried workers
This is the question that matters most to your paycheck. Employers generally choose one of two approaches:
Approach 1: Divide annual salary by 27
Your employer divides your stated annual salary by 27 instead of 26. Each check is about 3.7% smaller, but your annual gross remains the same. This is the most common approach because it keeps payroll costs predictable for the employer.
Approach 2: Keep per-check amount the same
Your employer continues dividing your annual salary by 26, keeping each check the same size. The 27th check is effectively a bonus — your annual gross increases by one check's worth. Some employment contracts specify this treatment, but it is less common because it raises the employer's total payroll cost.
Your employment contract or offer letter may specify which method applies. If it does not, ask your HR or payroll department well before the 27-period year begins. Use our biweekly pay calculator to model both scenarios.
How benefit deductions change in a 27-period year
This is where the 27th period creates the most confusion. Annual benefit costs (health insurance premiums, dental, vision, life insurance, HSA contributions, 401k matching caps) are typically divided across pay periods. In a 27-period year:
- Health insurance: If your annual premium is $6,000 and normally deducted across 26 periods ($230.77/check), spreading it across 27 periods lowers each deduction to $222.22. Some employers instead deduct the normal amount for 26 periods and skip the deduction on the 27th check.
- 401(k) contributions: The IRS annual contribution limit does not change in a 27-period year. If you set a per-check dollar amount, having 27 checks could push you over the limit. If you set a percentage, the system auto-adjusts. Verify with your payroll department.
- FSA/HSA contributions: Same issue — annual limits remain fixed. Ensure your per-check election does not overfund or underfund the account.
How tax withholding adjusts
The IRS withholding tables in Publication 15-T are designed to handle varying numbers of pay periods. Your employer uses the "biweekly" column, which calculates withholding per check based on that check's taxable wages. If each check is smaller (because salary was divided by 27), withholding per check is proportionally smaller — but the annual total stays about the same.
What you should not see is a significantly different total federal withholding for the year, because the tables are progressive and self-adjusting. However, minor differences can occur, which your tax return reconciles. For a deeper look at how withholding works, see the payroll mechanics guide.
How hourly workers are affected
Hourly workers are generally unaffected by the 27th period because they are paid for actual hours worked, not a divided annual salary. If the 27th pay period covers a normal two-week work schedule, hourly employees receive their regular pay for those hours. The 27-period issue is primarily a salaried employee concern.
What about weekly pay schedules?
Weekly pay schedules face a similar but more frequent issue: 365 ÷ 7 = 52.14 weeks. Some years have 53 weekly pay periods. The concept and employer response are identical — either divide salary by 53 or keep the per-check amount and pay more. For a comparison of all pay frequencies, see our semi-monthly vs. biweekly pay guide and paycheck frequency comparison calculator.
What to do in a 27-period year: checklist
- Check with HR early. Ask whether your company divides by 27 or keeps per-check amounts the same. Know this before the year starts.
- Review your benefit elections. Confirm that health insurance, FSA, HSA, and 401(k) contributions will not overshoot or undershoot annual limits.
- Adjust your budget. If checks are smaller, plan for lower per-period take-home. If you get an extra full check, decide whether to save or allocate it.
- Check year-end W-2. Verify that your total annual wages match your expected salary (or salary + one extra check, depending on the method used).
Questions
27 pay periods FAQ
Why do some years have 27 biweekly pay periods?
A biweekly pay cycle runs every 14 days, which produces 26 pay periods in most years (14 times 26 equals 364 days). Since a year has 365 days (or 366 in a leap year), an extra day accumulates each year. Roughly every 11 years, enough extra days accumulate that a 27th pay date falls within the calendar year. Whether it happens depends on which day of the week the first pay date falls.
Does a 27th paycheck mean more money for salaried workers?
That depends on how your employer handles it. Some employers divide your annual salary by 27 instead of 26, resulting in smaller per-check amounts but the same annual total. Others keep the per-check amount the same (annual salary divided by 26), which means your gross pay for the year increases by one check's worth. Ask your HR department which method your company uses.
How does a 27-pay-period year affect benefit deductions?
This is the biggest practical impact. If your annual health insurance premium is split across 26 checks and the year has 27 periods, your employer must decide whether to deduct premiums from all 27 checks (lower per-check deduction), skip the deduction on one check, or keep the same per-check deduction and collect the extra amount another way. Each approach affects your take-home pay differently.
Does a 27-pay-period year change my tax withholding?
The IRS withholding tables automatically adjust. Your employer uses the per-payroll-period tables from IRS Publication 15-T, which calculate withholding based on each check's gross amount and the number of periods in the year. In a 27-period year, each check's withholding is slightly lower because the annual salary is spread across more periods. Your total annual withholding should remain approximately the same.
Do hourly workers get an extra check in a 27-pay-period year?
Hourly workers are not directly affected the same way because they are paid for hours actually worked. If the 27th pay period covers a standard two-week work period, they receive their normal pay for those hours. The 27-pay-period concept mainly creates confusion for salaried employees whose annual salary must be divided across the pay periods.
- Sources: IRS Publication 15-T (Withholding Tables) · IRS 401(k) contribution limits.
- 🔄 Last updated July 31, 2026 · Tax year 2026
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