Immunization requirements to attend school (K-12) | Colorado Department of Public Health and Environment

Routine vaccination is important to protect health and prevent the spread of diseases such as measles, mumps, varicella (chickenpox), whooping cough, and others.

Vaccines are:

Powerful tools of prevention that help kids stay healthy and avoid disruptions from illness
Proven to be the best defense against many serious illnesses
Widely available for no or low cost in Colorado and across the U.S.
If you reside outside of Colorado, contact your local public health agency or your child’s health care provider for information on accessing vaccines in your area.

Families should be aware that children and adolescents with vaccine exemptions may be kept out of school or child care during a disease outbreak. The length of time will vary depending on the type of disease and the circumstances of the outbreak.

For example, if someone at your child’s school becomes sick with measles and your child is not up to date on their MMR vaccines, they may need to stay home from their program for at least 21 days.

This page is for school (K-12). Refer to the appropriate webpage for immunization requirements to attend child care, camp, or college or university.

Navigating Colorado’s vaccine requirements to attend school (K-12) is easy as 1, 2, 3!

1. Know the requirements.

Colorado law requires students attending Colorado public, private, or parochial kindergarten, elementary, or secondary schools through grade 12 to be vaccinated against certain diseases unless an exemption is on file at the school.

Vaccines required to attend school (K-12):

Hepatitis B (HepB)
Diphtheria, tetanus, pertussis (DTaP)*
Inactivated poliovirus (IPV)*
Measles, mumps, rubella (MMR)*
Varicella (chickenpox)*
Tetanus, diphtheria, pertussis (Tdap)**

*Students aged 4 through 6 years are required to have their final doses of DTaP, IPV, MMR, and varicella before kindergarten entry.

**For the current 2025-2026 school year, students are required to have a dose of Tdap vaccine before sixth grade entry. One dose of Tdap is required for sixth through 12th grades.

Starting in the 2026-2027 school year, Colorado law will require students to have one dose of Tdap vaccine before their first day of seventh grade.

If you have a student entering seventh grade in the 2026-2027 school year, you do not need to do anything if your student’s school has:

An immunization record showing that your student had an adolescent dose of Tdap on or after their 10th birthday, or
An in-process plan, signed by your child’s health care provider, showing that your child is catching up on their tetanus, diphtheria, and pertussis vaccine series, or
A complete Certificate of Medical or Nonmedical Exemption for the Tdap vaccine

See the Tdap parent letter, coming soon, for more information.

Before a student’s first day of school, Colorado law requires parents or guardians to provide each school their student attends with at least one of the following:

A: An immunization record showing that the student has received school-required vaccines and is up to date according to their age,

B: An in-process plan signed by the student’s health care provider showing that the student is in the process of catching up on missing vaccine(s) following the minimum intervals between doses described in the catch-up schedule,

C: A Certificate of Medical or Nonmedical Exemption for any missing doses of school-required vaccine(s)

To meet the requirements, students may have one or a combination of these documents for the different school-required vaccines.

For example, a student’s kindergarten immunization file at school could contain the following:

An immunization record showing they are up to date for HepB, DTaP, and IPV,
A Certificate of Nonmedical Exemption for MMR, and
An in-process plan showing they are catching up for varicella

A student who does not have the required immunization documents on file must be denied attendance in accordance with the law.

2. Prepare to meet the initial requirements.

Before your child’s first day of school, you must provide each school your child attends with the following documentation:

What’s needed for students who are up to date for school-required vaccines:

An immunization record from your child’s health care provider or other immunization provider that:

Shows your child has received school-required vaccines and is up to date according to their age and,
Includes the dates and types of immunizations administered

Vaccines required to attend school (K-12):

Vaccine name and abbreviation	Number of valid doses*
Hepatitis B (HepB)	3 doses
Diphtheria, tetanus, pertussis (DTaP)	5 doses
Polio (IPV)	4 doses
Measles, mumps, rubella (MMR)	2 doses
Varicella (chickenpox)	2 doses
Tdap (For the 2025-2026 school year, at sixth-grade entry. For the 2026-2027 school year, at seventh-grade entry).	1 dose

*If your child is or was behind on routine vaccines, the number of doses may vary:

Colorado’s school (K-12) immunization table can help you and your child’s health care provider determine if your child has the required doses.

What’s needed for students who are catching up on one or more school-required vaccine(s):

An immunization record showing which vaccines your child received (if any), and an in-process plan for children who started late or fell behind on vaccines required for school.

The immunization record must be from your child’s health care provider or other immunization provider and include the dates and types of immunizations administered.
The in-process plan (sample), signed by the child’s health care provider, must show that the child is in the process of catching up on missing vaccine(s) following the minimum intervals between doses described in the catch-up schedule.

Your child’s health care provider, immunization provider, or local public health agency can help your child catch up on the vaccines your child needs.

What’s needed for students who are missing school-required vaccines and whose parent or guardian wants to obtain an exemption for medical or nonmedical reasons:

A Certificate of Medical or Nonmedical Exemption

If you do not plan on vaccinating your child or they have a medical contraindication from receiving one or more school-required vaccines, you must follow Colorado’s process to obtain a certificate of exemption.

Certificates of Medical and Nonmedical Exemption must be obtained using Colorado’s process and documented on Colorado’s forms.

3. Continue to meet the requirements.

Parents or guardians must provide each school their child attends with updated immunization records before their child’s first day of school and in the following situations:

Before your child’s first day of kindergarten
Anytime your child receives a dose of a school-required vaccine
Annually, when required by your child’s school
Anytime your school requests a record because it was incomplete

Need tips on locating your child’s immunization record? Visit the finding a student’s immunization vaccine record for school webpage.

Children who have an in-process plan must follow the plan and provide immunization records as indicated on the plan until they are caught up on school-required vaccines.

Annually, parents and guardians who are exempting their child for nonmedical reasons must provide each school their student attends with a new Certificate of Nonmedical Exemption. Find more information on the exemptions to school-required vaccines webpage.