Unpaid leave and sabbaticals in the United States
Reviewed by Mellow Editorial Team, HR & payroll content team
Unpaid leave and sabbaticals have no single federal framework governing them — what an employee can take, and under what conditions, depends on a patchwork of federal law, state law, and employer policy. That makes it important for employers to understand each layer before setting their own rules.
What federal law actually requires
The main federal floor is the Family and Medical Leave Act (FMLA). Eligible employees at covered employers can take up to 12 weeks of unpaid, job-protected leave per year for qualifying reasons: a serious health condition, caring for a family member with one, the birth or placement of a child, or certain military-related needs. Some qualifying military situations extend that to 26 weeks.
FMLA coverage applies to employers with 50 or more employees. The employee must have worked for the employer for at least 12 months and logged at least 1,250 hours in the past year. During FMLA leave, the employer must maintain the employee's group health benefits and restore them to the same or an equivalent position when they return.
Outside FMLA, federal law has very little to say about unpaid leave. There is no federal statutory paid annual leave or sick leave. The Americans with Disabilities Act (ADA) can require unpaid leave as a reasonable accommodation, but the scope depends on the specific situation and employer size.
State law adds another layer
Many states have their own leave laws that go further than FMLA — lower employee thresholds, broader qualifying reasons, or longer durations. Some states also mandate paid family or medical leave funded through payroll contributions, which interacts with unpaid leave entitlements. California, New York, and Washington are among those with the most expansive state-level programs.
Before setting a leave policy, check the law in every state where you have employees. A policy that works fine for a team in Texas may fall short of requirements for the same role based in New Jersey.
Sabbaticals: entirely discretionary
Unlike FMLA leave, sabbaticals have no legal definition or requirement under US federal law. A sabbatical is whatever an employer decides it is — typically an extended leave, paid or unpaid, granted after a period of service, for rest, personal development, travel, or research.
Because sabbaticals are discretionary, the terms are entirely up to the employer: length, eligibility criteria, whether pay continues (in full, partial, or not at all), what happens to benefits during the leave, and whether the employee must return for a set period afterward. Some employers use a formal written agreement; that is good practice since it removes ambiguity about return obligations and what happens if the employee resigns instead of coming back.
One practical note: if you offer sabbaticals, document the program clearly and apply it consistently. An informal arrangement applied unevenly across employees can create discrimination risk.
Payroll and benefits considerations
Unpaid leave does not mean payroll disappears from your checklist. A few things to track:
Benefits continuation. FMLA requires you to maintain health coverage on the same terms as if the employee were working. For non-FMLA unpaid leave or sabbaticals, you can set your own rules, but you need to communicate them clearly — and check whether your benefits carrier has specific requirements.
FICA and income tax. Because the employee is not receiving wages during unpaid leave, there are no payroll tax withholding obligations for those periods. When they return and resume receiving pay, normal withholding resumes. If you pay any partial salary during a sabbatical, standard federal income tax withholding and FICA contributions apply to those amounts.
PTO and accrual. Decide in advance whether paid time off continues to accrue during unpaid leave. FMLA does not require accrual during leave, but your policy or a state law might.
Exempt employees and salary basis. For salaried exempt employees under the Fair Labor Standards Act, docking pay in partial-week increments can jeopardize their exempt status. Unpaid leave of a full week or more does not carry the same risk, but partial-week deductions need careful handling.
Building a clear policy
A workable leave and sabbatical policy covers: who is eligible, how far in advance notice is required, what documentation is needed, how benefits are handled, whether and how leave interacts with accrued PTO, and what the return-to-work process looks like.
For employers with workers across multiple states — a situation that has become far more common with remote hiring — how Mellow runs payroll across six countries illustrates why tracking local compliance requirements matters as much as the federal baseline. The same logic applies domestically: state-by-state differences are real, and a one-size policy often does not fit all locations.
Employment in the US is generally at-will, which means employees can resign and employers can end employment without cause — but neither fact eliminates the job-protection obligations that apply during FMLA leave. Keeping those obligations distinct from at-will rights is an easy area for employers to get confused, and worth being explicit about in any leave documentation.
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