(From Breast Cancer | Cancer Care Ontario)
Breast cancer is cancer that is found in the breast. It occurs when abnormal cells in the breast tissue multiply and form a tumour that may spread.
To learn more about breast cancer, visit the Canadian Cancer Society
(From Breast cancer screening and prevention | ontario.ca)
Cancer screening is testing done on people who are at risk of getting cancer, but who have no symptoms and generally feel fine.
The goal of breast cancer screening is to detect cancer early and provide treatment. A mammogram is an X-ray picture of the breast that can find small lumps or changes in your breast. A mammogram is currently the recommended test used to detect breast cancer.
Getting regular mammograms and proper follow-up testing for abnormal results are important because they can:
Find cancer early when it may be smaller and easier to treat
Lower the risk of dying from breast cancer
Mammograms are not perfect tests. Some cancers may also develop in the time between tests. It’s important to talk to your doctor or nurse practitioner about the benefits and limitations of testing for breast cancer.
First established in 1990, the Ontario Breast Screening Program (OBSP) provides high-quality breast cancer screening services to women, Two-Spirit, trans and nonbinary people living in Ontario. It is operated by Cancer Care Ontario and is funded by the Ontario Ministry of Health and Long-Term Care.
In October 2024, changes were made to breast screening services in Ontario. The Ontario Breast Screening Program expanded to offer screening to people ages 40 to 49. If you are in this age group, review Breast Cancer Screening for People Ages 40 to 49: What You Need to Know for more information.
The Ontario Breast Screening Program offers breast cancer screening to women, Two-Spirit people, trans people and nonbinary people ages 40 to 74 if they:
If you are 30 to 69 years old and confirmed high risk:
The Ontario Breast Screening Program (OBSP) recommends getting a mammogram with an MRI (a test that uses radio waves and a magnetic field to create different images of the breast) or ultrasound (a test that uses sound waves to create images of the breast) every year.
Talk with your doctor or nurse practitioner if you think you have family or medical history related to breast cancer or other criteria that may put you at high risk.
Breast Cancer Screening for People at High Risk | Cancer Care Ontario
If you are 40 to 49 years old:
Talk to your doctor, nurse practitioner or call Health811 to have a conversation about your risk of cancer, the potential benefits and risks of breast cancer screening, and your preferences and values for screening to determine if it is right for you.
You can self-refer for mammograms beginning at age 40. You will not need a doctor or nurse practitioner referral, and the service is covered by OHIP.
You can also go to myCANCERiQ to complete a cancer risk assessment.
You will be able to book an appointment for a mammogram by contacting your nearest Ontario Breast Screening Program location or calling 1-800-668-9304.
You can also book an appointment with your primary care provider to get a requisition for a mammogram.
Breast Cancer Screening for People Ages 40 to 49: What You Need to Know | Cancer Care Ontario
If you are 50 to 74 years old:
The Ontario Breast Screening Program recommends that most people in your age group get screened every 2 years with mammography. You do not need a doctor or nurse practitioner referral and the service is covered by OHIP.
To book an appointment, contact your nearest Ontario Breast Screening Program location or call 1-800-668-9304.
If you are over 74 years old:
Speak with your doctor or nurse practitioner about getting tested for breast cancer.
If you choose to get tested, you will need a referral for a mammogram from your doctor or nurse practitioner. This service is covered by OHIP with a referral.
All physicians and nurse practitioners in our Family Health Team are members of the OBSP.
When you go for your first mammogram, you will automatically be entered as part of the OBSP. You will receive reminder letters for your screening from the program, and copies of your test results are sent to your primary care provider to review.
People aged 40 and over who are at average risk may refer themselves to the OBSP. To self-refer, please by contacting your nearest Ontario Breast Screening Program location or call
People between the ages of 30 to 69 who are at high risk will need a referral from their doctor or nurse practitioner to be screened at an OBSP centre.
You can book an appointment by either:
Use Ontario Health’s Breast Screening Wait Times and Location Tool to find mammogram wait times, locations, accessibility information, hours of operation, and contact information.
Breast Cancer | Cancer Care Ontario
Breast cancer testing and screening (Ontario Ministry of Health)
Breast Cancer Screening for People at High Risk | Cancer Care Ontario
Cancer Care Ontario - Breast Cancer Screening for People Ages 40 to 49
What you should know about breast cancer screening
Edited June 26, 2026