This Version Posted: May 13, 2021

If you received your first dose of Pfizer, Moderna or AstraZeneca COVID-19 vaccine, you will need a second dose to be fully protected.

In Ontario, the second dose for these vaccines is now given up 112 days after the first dose.  

This timing affects everyone in Ontario, except for high-risk individuals, including: 

  • Residents of long-term care homes/retirement homes/elder care lodges/assisted living facilities. 
  • Adults who are First Nations, Inuit and Metis
  •  Highest-risk health care workers
  • Individuals with certain medical conditions:
    • Transplant recipients (including solid organ transplants and hematopoietic stem cell transplants)
    • Individuals with malignant hematologic disorders and non-hematologic malignant solid tumors receiving active treatment (chemotherapy, targeted therapies, immunotherapy), excluding individuals receiving solely hormonal therapy or radiation therapy
    • Individuals on dialysis

The Province of Ontario may add to this list from time to time, but no other exceptions are allowed unless the government adds to this list. 

If you are eligible for a shortened dose interval and are not able to book an appointment through your health care provider or pharmacy, follow the instructions to be added to the Click and Connect system and be placed on a booking list for a second dose appointment. 


If you booked your first dose of vaccine through the provincial booking system, you will have already received an appointment for your second dose. If you need to change your appointment, please call the provincial booking system booking number: 1-888-999-6488.

Please note: you may need to go to a different clinic location for your second dose appointment. Please check for updated vaccination clinic locations prior to your appointment.


The following information on booking an appointment for a second dose is for individuals who did NOT book their first vaccine dose through the provincial booking system.

Individuals who:
  • Received their first dose at an immunization clinic prior to March 25: you will be contacted directly about how to book an appointment for a second dose.
  • Received their first dose of vaccine through a hospital clinic: the hospital will contact you directly to book your appointment for second dose. If you are eligible for a shortened dose interval, the hospital will contact you about changes to your appointment.
  • Health care workers and essential caregivers who received their first dose of vaccine at a long-term care or retirement home: Check to see if there are plans for vaccination at your facility. If not, follow the instructions to be added to the Click and Connect system and be placed on a booking list for a second dose appointment.
  • Received their first dose of vaccine at an end-of-day dose at a Health Unit immunization clinic: you will need to book an appointment through the provincial booking system. The system does not yet allow second dose appointments to be booked. Check the website for updates on when the system will permit these appointments to be booked. If you are eligible for a shortened dose interval, follow the instructions to be added to the Click and Connect system and be placed on a booking list for a second dose appointment.
  • Received their first dose through a pharmacy or primary care provider after March 25: you will be provided a second dose appointment from the pharmacy or health care provider. 
  • Received their first dose of vaccine at a clinic held specifically for Indigenous adults: you will be contacted directly about how to book an appointment for a second dose.
  • Are receiving dialysis at a local hospital: the hospital will be in contact with you to schedule your second dose.

Additional Resources