What existed were targeted requirements for specific groups, plus private and local rules that created strong practical pressure in many settings:
- Federal government as employer: Biden administration rules required vaccination for most federal civilian employees, contractors, and certain programs (e.g., Head Start). Most of these ended by May 11, 2023, with the end of the federal public health emergency.
- Military: The Department of Defense required vaccination for service members starting in 2021. Congress ended the mandate via the 2023 National Defense Authorization Act; it was formally rescinded in early 2023. Thousands were discharged for non-compliance; later policies (including under the second Trump administration) allowed reinstatement with back pay for those who requested it.
- Healthcare workers: CMS (Centers for Medicare & Medicaid Services) required vaccination for staff at facilities participating in Medicare/Medicaid (hospitals, nursing homes, etc.). Some state-level healthcare mandates also applied. Many of these have since been relaxed or ended, though some targeted requirements lingered longer in certain places.
- Large private employers: OSHA’s vaccine-or-test rule for businesses with 100+ employees was blocked by the Supreme Court in January 2022 on the grounds that the agency lacked statutory authority for such a broad public-health measure. Private employers could (and some did) still set their own policies under existing employment law, subject to religious/disability accommodations.
- Colleges, schools, cities, and some states: Hundreds of colleges required vaccination for in-person attendance. A few cities (e.g., New York) and states imposed requirements for certain activities or workers. No states currently require COVID vaccines for K–12 school attendance, and a 2025 executive order restricted federal funding for schools that impose such mandates.
