Ontario Breast Screening Program (OBSP)

In operation since 1990, the OBSP is a province-wide organized breast cancer screening program managed by Cancer Care Ontario that offers eligible Ontario Women the benefits of regular screening1.  The OBSP provides routine high-quality screening mammography every two years for women age 50-74 years1.

As of 2011, the OBSP expanded to include a High Risk program with annual screening mammography and breast MRI for women age 30-69 years who are at high risk for breast cancer1.

Women age 75 and older

Women aged 75 and older may be screened in the OPBSP and benefit from the advantages of the program, however, they are encouraged to make a personal decision about breast cancer screening in consultation with their health care provider. After age 74, women will need a requisition for each screening mammogram from their health care provider.

Correspondence campaign

Cancer Care Ontario delivers personalized invitations, test results, recommendations for follow-up and reminders to return for cancer screening through its direct-mail correspondence program.

Women over age 74 who are screened in the OBSP will receive correspondence regarding normal screening results and follow-up of abnormal results will continue to be provided to their health care provider. However, these women will not receive recall letters or invitation letters from the OBSP in the future.

Because Your Family Matters campaign - October 2016

Central East Regional Cancer Program is encouraging women to put their health and well being first by booking a mammogram today. Oct. 20 is the Day of the Mammogram for participating OBSP sites in our region, offering longer hours of operation and inviting walk-ins. 

Average Risk


High Risk


General Resources


Screening Women Aged 40 to 49: The Controversy

The Canadian Task Force on Preventative Health Care (CTFPHC) recommends not routinely screening women aged 40 to 49 for breast cancer with mammography2.   The OBSP supports and is aligned with the CTFPHC guidelines and does not routinely screen women aged 40-49 years with mammography.


Patient Resources



  1. Cancer Care Ontario. Ontario Breast Screening Program Information for Healthcare Providers. Toronto, Canada, 2012.
  2. The Canadian Task Force on Preventive Health Care. "Recommendations on Screening for Breast Cancer in Average-risk Women Aged 40-74 Years." Canadian Medical Association Journal 183.17 (2011): 1991-2001.