Who this is for
Everyone in the rows below is at average risk. In the USPSTF's words, its recommendation applies to "cisgender women and all other persons assigned female at birth (including transgender men and nonbinary persons) 40 years or older at average risk of breast cancer", including those with dense breasts or a first-degree relative with breast cancer.
Different rules apply, and none of the rows below cover you, if you carry a BRCA1 or BRCA2 variant, had chest radiation at a young age, or have had breast cancer or a high-risk lesion on a previous biopsy. ACS recommends annual MRI plus mammography from about age 30 for those groups. ACR calls for every woman to have a formal risk assessment by age 25 to find out which set of rules applies.
Where the recommendations diverge
- USPSTF 40 to 74
- ACS 40 to 44
- ACS 45 to 54
- ACS 55 and older
- ACOG 40 and older
- ACR 40 and older
The USPSTF recommends biennial screening mammography for women aged 40 to 74 years.
Our note: This 2024 statement replaced the 2016 one, which recommended biennial screening from 50 to 74 and an individual decision in the 40s. USPSTF grades the evidence insufficient (I) for women 75 and older, and for supplemental ultrasound or MRI in dense breasts.
Women between 40 and 44 have the option to start screening with a mammogram every year.
Our note: ACS words this band as an option, not as a recommendation to screen.
Women 45 to 54 should get mammograms every year.
Women 55 and older can switch to a mammogram every other year, or they can choose to continue yearly mammograms. Screening should continue as long as a woman is in good health and is expected to live at least 10 more years.
Our note: ACS sets no stop age. It ties stopping to health and to a life expectancy of at least 10 years.
Today, the American College of Obstetricians and Gynecologists (ACOG) published an interim update to its clinical guidance, Practice Bulletin 179: Breast Cancer Risk Assessment and Screening in Average-Risk Women. The new update recommends that all individuals at average risk of breast cancer should begin screening mammography at 40 years of age.
Our note: Interval, same release: "ACOG continues to recommend screening mammography every one or two years based on an informed, shared decision-making process between patients and their clinicians." On stopping, Practice Bulletin 179, reaffirmed 2025, says: "Women at average risk of breast cancer should continue screening mammography until at least age 75 years." The full update is the Clinical Practice Update, Obstet Gynecol January 2025, doi 10.1097/AOG.0000000000005757.
The ACR continues to recommend annual screening starting at age 40 for women of average risk, but earlier and more intensive screening for high-risk patients.
Our note: The same statement calls for every woman to have a breast cancer risk assessment by age 25, to determine whether screening should begin before 40. ACR's average-risk recommendations are the 2021 ACR/SBI guideline, doi 10.1016/j.jacr.2021.04.021, which ACR links from its 30 April 2024 statement on the USPSTF recommendation. This 2023 release links the high-risk guideline, not the average-risk one.
Why they differ
The old fight is over. Until 2024 the USPSTF started at 50 and the rest started at 40, and most of the internet still prints that. All four bodies now say 40. What they still disagree on is how often and when to stop.
- Interval. USPSTF says every 2 years at every age, on the reasoning that biennial screening keeps most of the mortality benefit for considerably fewer callbacks and benign biopsies. ACR says every year, on its stated view that "the most lives are saved with this annual approach". ACS splits it: annual from 45 to 54, then the reader's choice. ACOG hands the interval to the patient and clinician together.
- Stopping. USPSTF's recommendation ends at 74 because no randomized trial of mammography enrolled women 75 or older, so it issues an I statement rather than a recommendation either way. ACS ties stopping to health and a 10-year life expectancy. ACOG says continue to at least 75. ACR and the Society of Breast Imaging say continue past 74 "unless severe comorbidities limit life expectancy".
The disagreement is not about the evidence, which is largely shared. It is about how much weight to put on the harms. USPSTF counts false positives, benign biopsies and overdiagnosis as costs that scale with how often you screen. ACR treats the deaths averted as the number that dominates. Both are reading the same trials.
4 documents set the numbers on this page. The oldest was published in 2023, the newest in 2026.
- https://www.uspreventiveservicestaskforce.org/uspstf/recommendation/breast-cancer-screening
- https://www.cancer.org/cancer/types/breast-cancer/screening-tests-and-early-detection/american-cancer-society-recommendations-for-the-early-detection-of-breast-cancer.html
- https://www.acog.org/news/news-releases/2024/10/acog-updates-recommendation-when-to-begin-breast-cancer-screening-mammography
- https://www.acr.org/News-and-Publications/Media-Center/2023/New-ACR-Breast-Cancer-Screening-Guidelines-call-for-earlier-screening-for-high-risk-women
We last re-read these sources on . How we verify.
What the test involves
You undress from the waist up. A technologist positions each breast on a plate and compresses it for a few seconds while the image is taken, usually two views per breast. The compression is uncomfortable and brief. The appointment is typically 20 minutes.
If the result is abnormal
Being called back is common and usually not cancer. A cohort analysis reported in the USPSTF statement put the 10-year cumulative probability of at least one false-positive result at 38.1 percent with biennial digital mammography and 35.7 percent with tomosynthesis, and the probability of a false-positive biopsy recommendation at 6.7 percent and 6.6 percent. A callback normally means extra images or an ultrasound; only some lead to a biopsy.
If you have dense breasts, US mammography facilities have been required since September 2024 to tell you so. Neither USPSTF nor ACS currently recommends for or against adding ultrasound or MRI on that basis alone: USPSTF calls the evidence insufficient, which is not the same as calling it useless.
More on this screening
Frequently asked questions
Should I start mammograms at 40 or 45?
As of 2024 every body on this page says 40. USPSTF, ACOG and ACR all name 40 as the start age, and ACS makes 40 to 44 an option before its own firm recommendation kicks in at 45. If a source tells you 50, check its date: that was the USPSTF position until April 2024 and it no longer holds.
Every year or every other year?
This is the live disagreement. USPSTF says every 2 years for everyone 40 to 74. ACR says every year. ACS says every year from 45 to 54, then your choice. ACOG says every 1 or 2 years, decided with your clinician. Annual screening finds slightly more cancers earlier and produces more callbacks and biopsies; that trade is the whole argument.
When do I stop?
No body publishes a hard stop. USPSTF's recommendation runs to 74 and then it says the evidence is insufficient, because no trial enrolled women 75 or older. ACS ties it to being in good health with at least 10 more years of life expected. ACOG says at least 75. ACR says keep going past 74 unless serious other illness limits life expectancy.
I was told I have dense breasts. Do I need an ultrasound or MRI too?
No body currently recommends it for dense breasts alone. USPSTF states that the evidence is insufficient to assess the balance of benefits and harms of supplemental ultrasound or MRI after a negative mammogram in dense breasts, and specifically says that is not a recommendation against it. Dense breasts do raise risk and do make mammograms harder to read, so it is a real conversation to have, just not a settled one.