Managing long-term sickness absence in the United States
Reviewed by Mellow Editorial Team, HR & payroll content team
Long-term sickness absence in the US is governed by a patchwork of federal and state laws rather than a single statutory framework. Employers need to navigate leave entitlements, pay obligations, and return-to-work requirements carefully — and the rules differ significantly depending on company size, state, and the nature of the illness.
What counts as long-term sickness absence
There is no universal legal definition, but most HR practitioners treat an absence lasting more than three to four consecutive weeks as long-term. At that point, several legal frameworks start to intersect: the Family and Medical Leave Act (FMLA), the Americans with Disabilities Act (ADA), state leave laws, and any short- or long-term disability insurance your company provides.
Understanding which frameworks apply to a given situation is the first practical step. They can overlap — an employee on FMLA leave may also be protected under the ADA, and state law may provide additional rights beyond the federal floor.
Federal protections you need to understand
FMLA applies to employers with 50 or more employees within a 75-mile radius. Eligible employees can take up to 12 weeks of unpaid, job-protected leave per year for a serious health condition. The leave can be taken continuously, intermittently, or as a reduced schedule. While on FMLA, you must maintain the employee's group health benefits on the same terms as if they had not taken leave.
Key FMLA obligations for employers:
- Notify the employee of their FMLA eligibility within five business days of learning the absence may qualify
- Provide the rights and responsibilities notice and a designation notice
- Keep the role (or an equivalent position) available on return
The ADA applies to employers with 15 or more employees. If the employee's condition qualifies as a disability — defined broadly as a physical or mental impairment that substantially limits a major life activity — you have a duty to provide reasonable accommodation. A leave of absence beyond what FMLA requires can itself be a reasonable accommodation, though there is no fixed length the law mandates. Courts and the EEOC have generally held that indefinite leave is not required, but determining what is reasonable involves a fact-specific, interactive process with the employee.
The ADA's interactive process matters: document every conversation, accommodation request, and decision you make. Failing to engage in that process is itself a liability risk.
Pay during long-term absence
The US has no federal statutory sick pay. What an employee receives during a long-term absence depends on:
- Employer-provided sick leave or PTO policy — employees may use accrued leave to receive pay
- Short-term disability (STD) insurance — typically replaces a percentage of salary for the first several weeks or months; this is a voluntary benefit many employers offer
- Long-term disability (LTD) insurance — kicks in after STD benefits are exhausted, often after 90 or 180 days; again, voluntary at the federal level
- State mandatory disability programs — California, New York, New Jersey, Rhode Island, Hawaii, and Washington have state-run short-term disability or paid family and medical leave programs with their own benefit rates and eligibility rules
From a payroll standpoint, any wages paid during leave are subject to the usual withholding: federal income tax, Social Security at 6.2% up to the annual wage base, and Medicare at 1.45% with no cap. Disability benefit payments from employer-funded plans are also generally taxable to the employee.
Managing the absence in practice
Staying in contact with an absent employee is both legally permitted and practically important — silence on both sides tends to make returns harder. A few ground rules:
- Keep contact reasonable and supportive, not pressuring
- Request medical certification where FMLA or ADA accommodation is involved; you are entitled to information about the functional limitations and expected duration, not a diagnosis
- Set a clear process for updating return-to-work timelines, ideally in writing
- If the employee's role genuinely cannot be held open indefinitely, document the business reason thoroughly before taking any action
If the employee exhausts FMLA leave and is still unable to return, do not assume you can immediately terminate. The ADA may require additional leave as accommodation. State laws may impose further obligations. Consult employment counsel before acting.
Return to work
A structured return-to-work plan reduces recurrence and limits legal exposure. Common elements include a phased return (reduced hours or duties initially), a fitness-for-duty certification if your policy requires one, and a brief meeting to agree on any ongoing accommodations.
Under the ADA, you may require a fitness-for-duty certification only if your policy or practice does so consistently — applying the requirement selectively creates discrimination risk. If an employee returns with lasting functional limitations, the interactive accommodation process continues: modified duties, adjusted schedules, or equipment changes may all be appropriate depending on the role.
Employment in the US is generally at-will, but terminating an employee because of a serious illness — without first exhausting your legal obligations under FMLA, the ADA, and any applicable state law — exposes your business to significant liability. The process matters as much as the outcome.
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