How to Calculate Your 12-Week FMLA Entitlement

To calculate FMLA leave, start with two numbers: your normal weekly work hours multiplied by 12 (that is your hour bank), and the 12-month period your employer uses to measure entitlement. A full-time employee working 40 hours a week has 480 FMLA hours; someone on a 35-hour schedule has 420; a 50-hour week produces 600.¹ Each hour of qualifying absence comes out of that bank until it resets, and when it resets depends entirely on which of four measurement methods your employer has chosen.

Confirm You Are Eligible First

The math only matters if you qualify. You must have worked for your employer for at least 12 months, logged at least 1,250 hours of service in the 12 months before leave starts, and work at a location where the employer has at least 50 employees within 75 miles measured by surface transportation along public roads.²³ Qualifying reasons include the birth or placement of a child, caring for a spouse, child, or parent with a serious health condition, your own serious health condition, and certain situations arising from a family member’s military deployment.⁴

The 12-Month Period That Governs Your Balance

Federal regulations allow employers to pick any one of four ways to define the 12-month window, and the choice must apply uniformly across the workforce.⁵ The method your employer uses is the single biggest variable in your calculation.

Calendar year: January 1 through December 31. Simple, but an employee can take 12 weeks at the end of one year and another 12 weeks starting January 1, effectively getting 24 weeks in a row.
Fixed 12-month period: any consistent year the employer selects, such as a fiscal year or your hire-date anniversary. Same stacking possibility as the calendar-year method.
Forward-looking period: the 12-month clock starts on the first day you take FMLA leave. If you first use leave on March 10, your period runs through March 9 of the following year, and the next period does not begin until you take FMLA leave again after that date.
Rolling lookback: each time you take leave, the employer looks back 12 months and subtracts whatever FMLA leave you used during that window. Your remaining balance is 12 weeks minus what you used in the prior 12 months.

The rolling lookback prevents leave stacking and is the method most employers prefer. The calendar year or fixed period give employees the most predictable reset dates.⁵ Your employer must tell you in writing which period it uses.⁶

When No Method Has Been Chosen

If your employer has never formally selected a method, the default is not the calendar year. The regulation requires the employer to use whichever method gives you the most leave for the situation at hand.⁵ If your employer is vague about which method applies, you may have more leave available than you think.

When an Employer Switches Methods

An employer changing methods must give all employees at least 60 days’ written notice. During the transition, employees get whichever method (old or new) yields more leave. The same 60-day notice applies when an employer picks a method for the first time. An employer cannot switch methods to reduce or eliminate leave you already have available.⁶

How Time Off Gets Subtracted From Your Bank

Continuous Leave

A full workweek off counts as one week of FMLA leave regardless of how many days fall in that workweek. Twelve straight weeks exhausts your entitlement.¹

Intermittent and Reduced-Schedule Leave

When you take leave in smaller chunks, only the time you actually miss counts. Convert your entitlement to hours by multiplying your normal weekly schedule by 12. Leave can be used in the smallest increment your employer tracks for other leave, as long as that increment is no larger than one hour. If payroll tracks in 15-minute blocks, you can use FMLA leave in 15-minute blocks.¹

Variable Schedules

When hours change significantly week to week and the employer cannot determine how many hours you would have worked, the employer uses a weekly average based on the hours scheduled over the prior 12 months, including any weeks you took other leave. The same averaging applies to seasonal workers.¹

Mandatory Overtime

Required overtime hours you miss for a qualifying reason count against your FMLA entitlement. Voluntary overtime you skip does not.¹ In jobs with heavy mandatory overtime, this can burn through hours faster than expected.

Holidays

A holiday during a full week of FMLA leave counts against your entitlement, because you were off for the entire week. During intermittent leave, or a partial week, a holiday only counts if you were actually scheduled to work that day and used FMLA leave instead.¹

Paid Leave Running Concurrently

FMLA leave is unpaid, but paid vacation, sick, or personal time can run at the same time. Your employer can require it, or you can choose it. Either way, paid leave runs concurrently, not in addition. If you fail to meet a requirement of the paid leave policy, you may lose the substitution but you keep the unpaid, job-protected FMLA time.⁷

If You and Your Spouse Work for the Same Employer

Spouses employed by the same company share a combined 12 workweeks for the birth of a child, placement of a child for adoption or foster care, and caring for a parent with a serious health condition. That is 12 weeks total between the two of you, not 12 each. Each spouse still has an individual 12-week entitlement for their own serious health condition or to care for a sick child or spouse.⁸

The 26-Week Military Caregiver Exception

The 12-week figure has one major exception. An eligible employee who is the spouse, child, parent, or next of kin of a covered servicemember with a serious injury or illness can take up to 26 workweeks in a single 12-month period.⁹ Covered servicemembers include current members of the Armed Forces (including National Guard and Reserves) undergoing medical treatment and veterans discharged under conditions other than dishonorable within the five years before the leave begins. The “next of kin” category runs in priority order: those granted legal custody, siblings, grandparents, aunts and uncles, then first cousins, unless the servicemember has designated someone else in writing. Spouses working for the same employer share a combined 26-week entitlement for this leave.⁸

Track Your Own Use

Do not rely entirely on your employer’s tracking. The single most important thing to confirm is which of the four 12-month methods your employer uses, because that determines when your leave resets and how much is available at any moment. If it is not in your handbook, ask HR in writing.

Keep your own log: dates, hours missed, and the qualifying reason for each absence. Intermittent leave is especially easy to lose track of; small blocks add up. Compare your log against any leave balance statements the employer provides and raise discrepancies quickly. Independent documentation is what makes your position credible if the two of you disagree about the count.

1
U.S. Department of Labor. Fact Sheet #28I: Counting Leave Use Under the Family and Medical Leave Act
2
U.S. Department of Labor. Fact Sheet #28: The Family and Medical Leave Act
3
eCFR. 29 CFR 825.111 – Determining Whether 50 Employees Are Employed Within 75 Miles
4
eCFR. 29 CFR Part 825 – The Family and Medical Leave Act of 1993 – Section 825.100
5
eCFR. 29 CFR 825.200 – Amount of Leave
6
U.S. Department of Labor. Fact Sheet #28H: 12-Month Period Under the Family and Medical Leave Act
7
eCFR. 29 CFR 825.207 – Substitution of Paid Leave
8
U.S. Department of Labor. Fact Sheet #28L: Leave Under the Family and Medical Leave Act for Spouses Working for the Same Employer
9
eCFR. 29 CFR 825.127 – Leave to Care for a Covered Servicemember With a Serious Injury or Illness