CDC Recommended Vaccine Schedule (Ages 0-6)

The immunization schedule is carefully designed to protect your baby at the earliest possible age, when they are most vulnerable to serious diseases.

Content reviewed against published CDC, AAP, ACIP, AAFP guidelines

Last reviewed: July 2026 · Editorial policy

Last reviewed:

Key takeaways

  • The CDC schedule protects against 14 serious diseases by age 2, with most doses given at routine well-child visits.
  • Each vaccine is timed to provide protection when your baby is most vulnerable and the immune system can respond effectively.
  • The schedule is endorsed by the AAP, AAFP, ACIP, and all major medical organizations.
  • Combination vaccines (like Pediarix) reduce total shots while providing the same protection.
  • If doses are missed, a catch-up schedule can get your baby back on track without restarting.

Vaccines by Age

At Birth

  • Hepatitis B (HepB) - 1st dose. Protects against a virus that causes liver disease and liver cancer.

2 Months

  • DTaP - 1st dose. Protects against diphtheria, tetanus, and pertussis (whooping cough).
  • IPV - 1st dose. Protects against polio.
  • Hib - 1st dose. Protects against Haemophilus influenzae type b (meningitis, pneumonia).
  • PCV15 or PCV20 - 1st dose. Protects against pneumococcal disease (meningitis, blood infections).
  • Rotavirus (RV) - 1st dose. Protects against severe diarrhea and dehydration.
  • Hepatitis B (HepB) - 2nd dose (given between 1-2 months).

This is when maternal antibodies begin to fade, making vaccination critical.

4 Months

  • DTaP - 2nd dose
  • IPV - 2nd dose
  • Hib - 2nd dose
  • PCV15 or PCV20 - 2nd dose
  • Rotavirus (RV) - 2nd dose

6 Months

  • DTaP - 3rd dose
  • PCV15 or PCV20 - 3rd dose
  • Rotavirus (RV) - 3rd dose (RotaTeq brand only; Rotarix is 2-dose)
  • Hepatitis B (HepB) - 3rd dose (given between 6-18 months)
  • IPV - 3rd dose (given between 6-18 months)
  • Influenza (Flu) - 1st dose annually starting at 6 months

12-15 Months

  • MMR - 1st dose. Protects against measles, mumps, and rubella.
  • Varicella - 1st dose. Protects against chickenpox.
  • Hepatitis A (HepA) - 1st dose. Protects against hepatitis A virus.
  • Hib - Booster dose
  • PCV15 or PCV20 - Booster dose

15-18 Months

  • DTaP - 4th dose

4-6 Years (Before Kindergarten)

  • DTaP - 5th dose
  • IPV - 4th dose
  • MMR - 2nd dose
  • Varicella - 2nd dose

These boosters ensure strong long-term protection before children enter school settings.

Why the Timing Matters

The schedule is not arbitrary. Each vaccine is timed based on:

  • When maternal antibodies wane and baby becomes vulnerable
  • When the immune system is mature enough to respond effectively
  • When the risk of disease exposure is highest
  • The minimum intervals needed between doses for optimal immunity

The Advisory Committee on Immunization Practices (ACIP) reviews all available evidence and updates recommendations when new data becomes available.

Related Vaccine Topics

Delayed Schedule Risks

Why delaying vaccines puts babies at risk

After Vaccination

What to expect and comfort measures

Premature Babies

Vaccination guidance for preemies

Vaccine Safety

How vaccines are tested and monitored

Frequently asked questions

Why does the schedule start at birth?
The Hepatitis B vaccine is given at birth because infants infected with Hepatitis B have a 90% chance of developing chronic infection, which can lead to liver cancer and liver failure later in life. Vaccinating at birth provides immediate protection before any potential exposure.
Why are so many vaccines given at 2 months?
At 2 months, maternal antibodies from pregnancy begin to wane, leaving babies vulnerable. The 2-month visit includes DTaP, IPV, Hib, PCV13, rotavirus, and HepB because these diseases are most dangerous for very young infants. Studies confirm that giving multiple vaccines at once is safe and does not overwhelm the immune system.
What if my baby misses a scheduled dose?
If your baby misses a dose, you do not need to restart the series. Your pediatrician will use the CDC catch-up schedule to get back on track. The key is to resume as soon as possible — every day without protection is a day of vulnerability.
Can preemies follow the same schedule?
Yes. The AAP and CDC recommend that premature babies follow the same immunization schedule based on their chronological (actual) age, not their adjusted age, with the exception of Hepatitis B for babies under 2,000 grams at birth, who may need a delayed first dose.
Are combination vaccines safe?
Yes. Combination vaccines (like Pediarix, which combines DTaP, IPV, and HepB) reduce the number of shots while providing the same protection. They undergo the same rigorous safety testing as individual vaccines. The AAP and CDC support their use.

Bottom line

The CDC immunization schedule is the product of decades of research and is endorsed by every major medical organization. It is designed to protect your baby from 14 serious diseases at the earliest safe age, when they are most vulnerable.

Keeping up with vaccines can feel overwhelming, but your pediatrician's office tracks it for you. Each well-child visit is an opportunity to stay on schedule.

Our commitment to accuracy

Every page is reviewed against published guidelines from authoritative medical organizations including the CDC, WHO, AAP, ACOG, ASHA, and NIH.

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