Boosters and Third Doses

Booster shots for the Pfizer COVID-19 Vaccine


The Centers for Disease Control and Prevention (CDC) now recommends booster shots for certain individuals at least six months after receiving their second dose of the Pfizer COVID-19 vaccine.


According to the CDC guidance, eligible individuals should receive a booster if they are:



The CDC says individuals may receive a booster if they are age:


  • 18 to 49 with underlying medical conditions.
  • 18 to 64 and face increased risk for COVID-19 exposure and transmission because of occupational or institutional settings. This applies to frontline essential workers, including healthcare professionals; first responders; teachers and other school and day care staff; food and agriculture workers; corrections staff; and employees of the U.S. Postal Service, public transit, and grocery stores.


People who received the Moderna or Johnson & Johnson vaccines are not yet eligible for booster shots. Research studies for these vaccines are still being evaluated.


However, if you received the Pfizer vaccine, the second dose was at least six months ago, AND you are in one of the groups identified by the CDC (above), you are eligible to receive a booster.


You are not required to receive a Pfizer booster shot from the same site where you received your prior vaccine doses.


New Jersey has over 1,600 vaccination sites, more than 1,000 of which offer the Pfizer vaccine. Many sites have walk-in availability and extended hours.



How to schedule a COVID-19 Vaccine


To find a vaccination site and book an appointment online, including appointments at Penn Medicine Princeton Medical Center (PMC), visit or call the state’s Vaccine Call Center at 1.855.568.0545.

At this time the New Jersey vaccine scheduling system (NJVSS) does not permit scheduling a booster shot or third dose appointment, but this function will be available soon. If you are eligible for a booster shot or third dose, please register on NJVSS and bring your vaccine card and driver’s license.



Vaccine Clinics at Princeton Medical Center


PMC will host vaccine clinics for individuals who need first, second or third doses of the Pfizer COVID-19 and Moderna vaccines, as well as those who need a booster shot of the Pfizer COVID-19 vaccine. The vaccine clinics will be held in the Schreyer Education Center —located at One Plainsboro Road in Plainsboro, NJ (Building D in the Campus Map here)— and will take place each Friday, from 9 a.m. to 1 p.m., through November 5. Individuals may park in Lot P2 for direct access to the clinic.


Walk-ins are welcome, but you may also schedule an appointment through the New Jersey Vaccine Scheduling System (NJVSS). If you have not already registered with NJVSS, visit After registering, you will be able to book an appointment at PMC or any other location that uses the system.


If you have any questions about COVID-19 vaccines at PMC, please email or call the voicemail 609.853.7444. You can expect a return call within 3-4 business days.



Third doses


Booster shots should not be confused with third doses of the Pfizer or Moderna vaccine, which the CDC recommends for individuals with moderately to severely compromised immune systems at least 28 days after receiving their second dose. Third doses for immunocompromised individuals are also available at PMC and other vaccine sites.

COVID-19 Vaccines for Moderately to Severely Immunocompromised People | CDC



Frequently Asked Questions


The New Jersey Department of Health (NJDOH) has created useful guides for individuals who may have questions regarding booster shots and third doses of COVID-19 vaccines. Please click on the links below to access these NJDOH materials.


Do I need a booster of the COVID-19 vaccine?

Do I need a third dose of the COVID-19 vaccine?

What’s the difference between a third dose and a booster of the COVID-19 vaccine?

What do I need to know about third doses and boosters of the COVID-19 vaccine?