How school-entry rules work, why they vary by state, and how exemption policies differ
A federal vaccine recommendation is not the same as a state school-entry requirement. The CDC and its Advisory Committee on Immunization Practices (ACIP) develop recommendations for how vaccines should be used in the general U.S. population. Once adopted by the CDC Director, those recommendations become official CDC policy and can trigger important federal effects, including insurance coverage rules and vaccine-program eligibility.
School-entry requirements are different. States — not the federal government — establish which vaccines are required for children to attend school, and states also define exemptions and enforcement rules. That is why a vaccine can be federally recommended and federally covered without automatically becoming a school-entry requirement in every state.
All 50 states and Washington, D.C. currently require certain vaccines for students attending school. This authority comes from the states' role in protecting public health, which courts have long upheld.
Upheld a state's authority to enforce compulsory vaccination, ruling that individual liberty is subject to reasonable restraints for the common welfare during a public health threat.
Specifically affirmed that school systems may exclude children who do not meet vaccination requirements, even in the absence of an active outbreak.
These decisions remain foundational precedents in discussions of state vaccination authority and school-entry requirements.
States do not all convert federal recommendations into school-entry rules the same way. There are two main approaches.
In some states, the state legislature must vote before a vaccine can be added to the school-entry list. This means elected officials directly control which vaccines are required and which exemptions are available.
Some states have gone further by restricting vaccine mandates through legislation. Idaho, for example, enacted the Idaho Medical Freedom Act (SB 1210, signed April 2025, effective July 1, 2025), which prohibits government entities, schools, and businesses from requiring medical interventions including vaccines.
In other states, a state health board or department has standing authority to update school-entry requirements based on new federal recommendations without a separate legislative vote. In these states, requirements can change through an administrative process rather than a public legislative debate.
This difference determines whether elected officials or appointed officials control the decision. In states with administrative adoption, a new CDC recommendation can become a school-entry requirement more quickly and with less public input. In states with legislative adoption, a separate bill or vote is required before any change takes effect.
While all states require certain vaccines for school entry, every state also provides at least one pathway for exemption. Exemption availability and procedures vary significantly by state.
Available in all 50 states. A licensed physician certifies that a required vaccine is or may be medically harmful for a specific child due to a contraindication or other health condition.
Available in 44 states as of early 2026 (per NCSL's Routine Child Vaccination tracker; this count can shift with legislative activity). These exemptions allow parents or guardians to decline vaccination based on sincerely held religious beliefs. Procedures vary — some states require a signed statement, others require notarization or periodic renewal.
Five states have historically not allowed religious exemptions: California, New York, Maine, Mississippi, and West Virginia. This landscape is actively changing. In West Virginia, Governor Patrick Morrisey issued an executive order in January 2025 allowing religious exemptions, and a circuit court granted a supporting injunction in November 2025. However, the West Virginia Supreme Court stayed that ruling in December 2025, and the case remains unresolved as of April 2026.
Available in 15 states as of early 2026 (per NCSL). These exemptions allow parents to decline vaccination based on personal, moral, or philosophical objections rather than religious beliefs. Some states that offer philosophical exemptions also cover religious objections within the same exemption category.
In 2025, North Dakota created formal opt-out procedures for health, religious, or philosophical reasons across school and child care settings (per NCSL).
Procedures for obtaining an exemption vary by state and may include physician certification, signed statements, educational requirements, counseling sessions, or periodic renewal. Some states have strengthened procedural requirements in recent years to ensure that exemption requests reflect informed decisions.
What happens when a child is missing required vaccines and no exemption is filed varies by state. Common enforcement mechanisms include:
The child may not attend until vaccination requirements are met or an exemption is filed. This is the most common enforcement tool.
Some states allow a grace period — typically 30 days — for students to begin a required vaccine series while attending school.
During an outbreak of a vaccine-preventable disease, students with exemptions may be temporarily excluded from school until the outbreak is resolved, even if they have a valid exemption on file.
Schools typically review immunization records at enrollment and may conduct periodic audits. Requirements for documentation format and verification vary by state.
Tennessee, for example, has exempted fully online, self-paced private schools from certain vaccination requirements (per NCSL), reflecting how enforcement rules can differ based on school type and setting.
Federal recommendations and state requirements do not always align. A vaccine can appear on the CDC schedule without being required by a given state, and states can maintain requirements that go beyond current federal recommendations. This divergence became particularly significant in 2025 and 2026.
Following a presidential memorandum, HHS/CDC implemented major changes to the childhood immunization schedule through a decision memorandum dated January 5, 2026. These changes reduced the number of diseases targeted by routine recommendations from 17 to 11 and the number of routine vaccines from 13 to 7. Six vaccines — for rotavirus, COVID-19, influenza, hepatitis A, hepatitis B, and meningococcal disease — were no longer recommended for routine use by all children. Some were moved to recommendations only for higher-risk groups, while others were moved to shared clinical decision-making, meaning the decision is made between the parent and provider rather than as a universal recommendation.
A growing number of states responded by announcing they would not follow the revised federal recommendations. According to KFF:
Most of these states have pointed to the American Academy of Pediatrics (AAP) recommendations, prior versions of the CDC schedule, or their own state-level expert panels as their primary reference.
On March 16, 2026, a U.S. District Court issued a preliminary injunction staying the January 2026 schedule changes and related administrative actions. As a result, the schedule in effect prior to the January 2026 changes currently serves as the federal baseline for insurance coverage and federal programs. States that had already announced their own guidance continue to follow their independent decisions regardless of the court's stay.
The full impact of these shifts may not be clear until later in 2026, when states translate their vaccine recommendations into school-entry requirements for the 2026-2027 academic year.
Note: This section reflects the situation as of April 2026. Federal vaccine policy is in an active period of administrative and legal transition. For the federal side of these changes, see U.S. Federal Vaccine Policy. For emergency-era mechanisms that operate outside the standard path, see Emergency Powers and Pandemic Policy (planned page).
| Topic | What varies |
|---|---|
| Required vaccines | Which specific vaccines are required for school or daycare entry |
| Adoption process | Whether the legislature or a health board controls the school-entry list |
| Exemptions | Whether religious and/or philosophical exemptions are available, and what procedures apply |
| Enforcement | Exclusion rules, provisional admission periods, outbreak policies, and documentation requirements |
For current state-by-state data, see the primary sources below.