Who this is for
Everything below applies to adults at average risk, which all three bodies define by exclusion: no personal history of colorectal cancer or certain polyps, no family history of it, no inflammatory bowel disease, no hereditary syndrome such as Lynch or familial adenomatous polyposis, and no prior abdominal or pelvic radiation.
If any of those apply to you, none of these rows is your schedule. You may need to start earlier than 45, screen more often, and use colonoscopy specifically rather than a stool test.
Screening is also for people with no symptoms. Rectal bleeding, a change in bowel habits, or unexplained weight loss or anemia is a reason to be evaluated now, not a reason to book a screening test.
Where the recommendations diverge
- USPSTF 45 to 49
- USPSTF 50 to 75
- USPSTF 76 to 85
- ACS 45 to 75
- ACS 76 to 85
- ACP 50 to 75
The USPSTF recommends screening for colorectal cancer in adults aged 45 to 49 years.
Our note: New in 2021. The page states it plainly: the USPSTF expanded the recommended ages to 45 to 75 years, having previously started at 50.
The USPSTF recommends screening for colorectal cancer in all adults aged 50 to 75 years.
Our note: Listed strategies: HSgFOBT or FIT every year; stool DNA-FIT every 1 to 3 years; CT colonography every 5 years; flexible sigmoidoscopy every 5 years; sigmoidoscopy every 10 years plus annual FIT; colonoscopy every 10 years.
The USPSTF recommends that clinicians selectively offer screening for colorectal cancer in adults aged 76 to 85 years. Evidence indicates that the net benefit of screening all persons in this age group is small.
Our note: A grade C is not a recommendation against. It asks the clinician to weigh overall health, prior screening history and the patient's preferences case by case.
The American Cancer Society recommends that people at average risk of colorectal cancer start regular screening at age 45.
Our note: A footnote marker after "average risk" is dropped. On stopping, the same page says: "People who are in good health and with a life expectancy of more than 10 years should continue regular colorectal cancer screening through age 75."
For people ages 76 through 85, the decision to be screened should be based on a person's preferences, life expectancy, overall health, and prior screening history.
Our note: Above that band ACS is categorical: people over age 85 should no longer get colorectal cancer screening.
In this updated guidance, ACP suggests that clinicians: Start screening for colorectal cancer in asymptomatic average-risk adults at age 50 years. ... Stop screening for colorectal cancer in asymptomatic average-risk adults older than 75 years or in asymptomatic average-risk adults with a life expectancy of 10 years or less.
Our note: Two non-adjacent bullets from ACP's own list, joined by " ... ". The bullet the ellipsis omits is ACP's most distinctive: "Consider not screening asymptomatic average-risk adults between the ages of 45 to 49. Clinicians should discuss the uncertainty around benefits and harms of screening in this population." The lead-in is quoted because it carries the force: ACP suggests, it does not direct, which is why the grade cell is empty. ACP also rules out stool DNA, CT colonography, capsule endoscopy, urine and serum tests. Guidance statement: Annals of Internal Medicine, doi 10.7326/M23-0779.
Why they differ
There is a five-year band, 45 to 49, where two of these bodies tell you to screen and the third tells your doctor to consider not screening you. That is not a nuance, it is opposite advice, and it is the single most useful thing on this page.
- USPSTF (2021) gives 45 to 49 a grade B, meaning screen. It expanded downward from 50 on modeled life-years gained against rising early-onset incidence.
- ACS (page revised 2026) starts regular screening at 45 with no qualifier.
- ACP (2023) suggests clinicians "consider not screening asymptomatic average-risk adults between the ages of 45 to 49" and discuss the uncertainty with them. Its stated reasoning, in its own words: "The net benefit of colorectal cancer screening is much less favorable in average-risk adults between ages 45 to 49 years than 50 to 75 years. Although there has been a small increase in CRC incidence among individuals aged 45 to 49 years, the incidence is much lower than in individuals aged 50 to 64 years and 65 to 74 years."
They also differ on the test menu, and it is the same argument in a different form. ACP names a short list and explicitly rules out stool DNA and CT colonography, on the grounds of harms, cost and follow-up burden. USPSTF and ACS include both. ACP puts FIT at every 2 years; USPSTF and ACS put it at every year.
Both positions are consistent, and they diverge on how much weight to give a small absolute increase in incidence in the late 40s against the harms, procedures and cost of screening ten million more people.
3 documents set the numbers on this page. The oldest was published in 2021, the newest in 2026.
- USPSTF recommendation
- American Cancer Society recommendation
- American College of Physicians recommendation
We last re-read these sources on . How we verify.
What the test involves
A stool test is a kit you use at home and mail back: FIT needs one sample and no diet or medication changes, stool DNA needs a whole bowel movement. A colonoscopy needs a day of bowel prep, which most people find worse than the procedure, and is done under sedation; polyps found are removed during the same appointment. Sigmoidoscopy examines only the lower colon and needs less preparation. CT colonography is a scan, with the same prep and no sedation, and any finding still means a colonoscopy afterward.
If the result is abnormal
Any abnormal result from a stool test, CT colonography or sigmoidoscopy leads to a colonoscopy, and the timeliness of that follow-up is what makes the whole strategy work. ACS states it directly: if a person chooses a test other than colonoscopy, any abnormal result should be followed up with a timely colonoscopy.
A colonoscopy that finds and removes polyps sets your next interval, which will be shorter than 10 years and is decided by the number, size and type of the polyps. At that point you are no longer on the average-risk schedule on this page.
More on this screening
Frequently asked questions
Do I start at 45 or 50?
USPSTF and ACS say 45. ACP suggests clinicians consider not screening average-risk adults aged 45 to 49 and discuss the uncertainty instead. All three are current, so a clinician who offers you a test at 45 and one who suggests waiting are both following a published US guideline. Ask which one they are following and why.
Is a stool test as good as a colonoscopy?
They are different trades, not better and worse. A colonoscopy every 10 years is one prep and one sedation per decade and removes polyps during the same visit. Annual FIT is no prep and no sedation but has to be repeated every year to work, and an abnormal result means a colonoscopy anyway. All three bodies say the important thing is to be screened by some accepted method.
What about the blood tests I have seen advertised?
ACS addresses them directly and is not enthusiastic: blood-based screening tests are not preferred screening options at this time, and should only be used if you are not willing to do a stool test or a visual exam. ACP goes further and says clinicians should not use serum tests for colorectal cancer screening at all. A positive result still means a colonoscopy.
When do I stop?
All three treat 75 as the edge rather than a wall. USPSTF grades 76 to 85 a C, meaning selectively offered. ACS says the decision in that band turns on preference, life expectancy, health and prior screening, and that nobody over 85 should be screened. ACP suggests stopping after 75, or sooner if life expectancy is 10 years or less.