The FMLA Rolling 12-Month Period and the Three Other Ways to Count the Leave Year

Where the Rule Comes From

An eligible employee is entitled to a total of 12 workweeks of leave "during any 12-month period" for the reasons listed in 29 CFR 825.200(a). The statute does not define that period. Section 825.200(b) lets the employer pick one of four definitions:

1. The calendar year.
2. Any fixed 12-month leave year, such as a fiscal year, a year required by state law, or a year starting on the employee's anniversary date.
3. The 12-month period measured forward from the date an employee's first FMLA leave begins.
4. A "rolling" 12-month period measured backward from the date an employee uses any FMLA leave.

Whichever one you choose must be applied "consistently and uniformly to all employees" (§ 825.200(d)(1)), with one exception for multi-state employers covered later.

The employee must be eligible first; see our article on FMLA eligibility requirements, and the Glossary of FMLA Terms for the vocabulary used below.

The Four Methods Side by Side

To compare them, take one set of facts. Maria (an example) starts 12 weeks of continuous FMLA leave on Monday, October 5, 2026, and returns after Friday, December 25, 2026. When can she next take protected leave?

Calendar year and fixed year: simple, but leave can be stacked

Under the first two methods, an employee is entitled to up to 12 weeks at any time in the fixed period. The regulation says outright what that allows: "An employee could, therefore, take 12 weeks of leave at the end of the year and 12 weeks at the beginning of the following year" (§ 825.200(c)). With a calendar-year policy, Maria could finish her 12 weeks on December 25, 2026, and start a second protected 12-week block on January 1, 2027, if she has a qualifying reason for it. Only the last few days of December fall outside FMLA protection.

That is the trade: easy to explain and track, at the cost of possible stacking.

Measured forward: individual leave years

Under § 825.200(c), the employee is entitled to 12 weeks "during the year beginning on the first date FMLA leave is taken; the next 12-month period would begin the first time FMLA leave is taken after completion of any previous 12-month period." Each employee has a personal leave year. The burden is tracking a different start date for every employee who has taken leave.

One place this method is not optional: military caregiver leave. The 26-workweek entitlement is always measured in a "single 12-month period" that runs forward from the first day the employee takes leave to care for the covered servicemember, regardless of the method you use for other FMLA reasons (§ 825.200(f)).

Rolling backward: no stacking, more math

Under the rolling method, "each time an employee takes FMLA leave the remaining leave entitlement would be any balance of the 12 weeks which has not been used during the immediately preceding 12 months" (§ 825.200(c)). There is no reset date. The balance is recalculated every day leave is used.

How to Calculate the FMLA Rolling 12-Month Period

The procedure is the same every time:

1. Identify the first day of the leave being requested.
2. Look back 12 months from that day.
3. Add up all FMLA leave the employee used inside that window.
4. Subtract the total from 12 workweeks. The remainder is what is available on that day.
5. For leave that continues over several days or weeks, repeat for each day, because older leave may be dropping out of the window as new leave is used.

Example 1: blocks of leave

Dana (an example) works for an employer that uses the rolling method. Her FMLA history:

• 4 weeks beginning Monday, March 2, 2026 (through March 27).
• 4 weeks beginning Monday, July 6, 2026 (through July 31).

On Monday, November 2, 2026, she needs leave for surgery.

• Look-back window: The 12 months before November 2, 2026.
• Leave used in the window: 4 weeks (March) + 4 weeks (July) = 8 weeks.
• Available: 12 - 8 = 4 weeks.

Dana's surgeon certifies six weeks of recovery. Only the first four weeks, November 2 through November 27, are FMLA-protected. The remaining two weeks are a question for your other leave policies, state law, and the ADA, not a point at which the analysis ends.

After November 27, Dana has used 12 weeks in the preceding 12 months and has no FMLA leave available. Following the regulation's example, she begins to regain it on March 2, 2027, the anniversary of the first day used: "the employee would recoup (and be entitled to use) one additional day of FMLA leave each day for four weeks." So:

This is why the regulation warns that under the rolling method employees "may fall in and out of FMLA protection."

Example 2: intermittent leave in hours

The entitlement is 12 workweeks, and the employee's actual workweek is the basis for converting it (§ 825.205(b)). For someone who normally works 40 hours a week, 12 workweeks is 480 hours.

Sam (an example) works 40 hours a week and takes intermittent FMLA leave for a chronic condition. He calls out for 8 hours on Thursday, October 15, 2026.

• Look-back window: The 12 months before October 15, 2026.
• FMLA hours used in the window, from the time records: 452.
• Available on October 15: 480 - 452 = 28 hours. The 8-hour absence is protected, leaving 20.

Now suppose 16 of those 452 hours were used on October 19 and 20, 2025. When the look-back moves past those dates in October 2026, those 16 hours drop out and Sam's balance rises by 16 without any reset. A tracker that only subtracts will show Sam as exhausted before he is; a rolling-method tracker has to add back as well. Our articles on managing FMLA leave systems and process and the FMLA intermittent leave guide cover the tracking mechanics.

Holidays Inside the Count

Under any method, § 825.200(h) governs what counts as a week used. A holiday inside a full week of FMLA leave does not reduce the count. When leave is taken in increments of less than a week, the holiday does not count unless the employee was otherwise scheduled and expected to work that day. A January 2026 DOL opinion letter (FMLA2026-1) applied the same logic to partial-week school closures.

If You Never Chose a Method

Section 825.200(e) is short and expensive: if the employer fails to select one of the options, "the option that provides the most beneficial outcome for the employee will be used."

In practice, each request is tested against all four methods and the best one for that employee wins. Maria, from the table above, would get the calendar-year method and could stack leave.

A policy that says only "12 weeks of leave in a 12-month period" has not chosen a method. Name it in the regulation's words. The rights and responsibilities notice must also tell the employee "the applicable 12-month period for FMLA entitlement" (§ 825.300(c)(1)(i)), and DOL's optional Form WH-381 has four checkboxes for exactly this purpose. Our FMLA forms guide for employers explains where that box sits, and the article on employer notice duties and deadlines covers when the notice is due.

Changing Methods: The 60-Day Notice

You may change methods, or select one for the first time after operating without one, under these conditions:

• Notice: "At least 60 days notice to all employees" (§ 825.200(d)(1)). An employer that never selected a method may select one "only by providing the 60-day notice to all employees" (§ 825.200(e)).
• Transition: Employees must "retain the full benefit of 12 weeks of leave under whichever method affords the greatest benefit to the employee" during the transition. For a first-time selection, any employee who needs leave during the 60 days may use the option most beneficial to that employee; the new method takes effect at the end of the 60 days.
• Purpose: "Under no circumstances may a new method be implemented in order to avoid the Act's leave requirements."

In practice: set an effective date at least 60 days out, send written notice to all employees and keep proof, update the policy and your WH-381 template, and during the transition calculate each request under both methods and apply the more generous result.

Multi-State Employers

Uniformity has one stated exception. Where a state with its own family and medical leave statute requires a single measuring method, a multi-state employer "may comply with the State provision for all employees employed within that State, and uniformly use another method provided by this regulation" for everyone else (§ 825.200(d)(2)).

State requirements differ and change. Confirm with each state's labor or paid-leave agency which states currently mandate a specific 12-month measuring method for state family or medical leave. Our multi-state leave laws compliance guide covers the broader coordination problem.

Tell the Employee Which Period Applies

The amount of leave counted must be given in the FMLA designation notice when it is known, or on request (no more often than once in a 30-day period in which leave was taken) when it is not (§ 825.300(d)(6)). Under the rolling method, be ready to show the look-back window and the hours inside it.

Leave-year questions rarely arrive alone. The employee with two weeks of FMLA left often also has a state leave balance, a possible ADA accommodation, or a workers' compensation claim. The Leave and Accommodation Management course is a two-day, instructor-led workshop for experienced administrators that works through those overlaps with case studies and exercises.

Frequently Asked Questions

The Bottom Line

Choose a method on purpose, write it into the policy in the regulation's words, check the matching box on the eligibility and rights notice, and make sure your tracking system calculates it the same way a person would by hand. If you use the rolling method, test that the system adds leave back as old absences age out. If you have never chosen, you are already operating under the employee-favorable default, and the fix is a selection plus 60 days' notice.

For the full picture, start with our FMLA Guide and work through the FMLA Compliance Checklist. When the leave-year question is tangled up with ADA, workers' compensation, PWFA, or state leave, the Leave and Accommodation Management course is built for exactly those cases.

This article is general education, not legal advice for a specific situation.