I want the longest interval.
Colonoscopy has a 10-year screening interval after a normal high-quality exam for an average-risk person.
Average-risk screening options
Compare colorectal cancer screening tests
Current American Cancer Society guidance recommends regular screening beginning at age 45 for people at average risk. The preferred options include stool-based tests and visual exams; blood-based tests are an alternative when preferred tests are declined or not completed.
Important: The intervals below are for average-risk screening after a negative result. If you have symptoms, prior colorectal cancer, certain prior polyps, inflammatory bowel disease, a hereditary syndrome, or a significant family history, these schedules may not apply.
| Test | Where | Typical ACS interval | Prep | Sedation | Can remove polyps? | If abnormal |
|---|---|---|---|---|---|---|
| FIT | Home | Every year | No bowel prep | No | No | Colonoscopy |
| High-sensitivity gFOBT | Home | Every year | No colonoscopy prep | No | No | Colonoscopy |
| Multi-target stool DNA | Home | Every 3 years | No bowel prep | No | No | Colonoscopy |
| Multi-target stool RNA | Home | Every 3 years | No bowel prep | No | No | Colonoscopy |
| Colonoscopy | Endoscopy facility | Every 10 years | Yes | Commonly | Yes, many polyps | Biopsy/removal may occur during exam |
| CT colonography | Imaging center | Every 5 years | Usually yes | No | No | Colonoscopy |
| Flexible sigmoidoscopy | Medical facility | Every 5 years | Varies | Usually not | Limited | Colonoscopy may be needed |
| Blood-based screening | Lab/clinic | Depends on approved test | No bowel prep | No | No | Colonoscopy |
Why blood tests are separated: ACS 2026 recognizes blood-based screening but does not list it as a preferred option because it is less effective at detecting precancerous growths. ACS advises using a blood-based option when a person is not willing to complete a preferred stool-based or visual exam.
How to choose
There is no single best test for every average-risk person.
I strongly prefer an at-home test.
FIT, high-sensitivity gFOBT, stool DNA, and stool RNA are home-based options. They must be repeated on schedule.
I want a test that can remove polyps.
Colonoscopy can find and remove many polyps during the same procedure.
I want to avoid sedation.
At-home stool tests, CT colonography, and most sigmoidoscopy screening do not require the sedation commonly used with colonoscopy.
I had an abnormal non-colonoscopy test.
That screening process is not complete until the recommended follow-up colonoscopy is performed.
I have symptoms or higher risk.
Do not simply pick an average-risk test from this table. Your clinician may recommend a diagnostic exam or a different screening/surveillance plan.
Two guideline systems
Why you may see different intervals online
Professional organizations sometimes recommend slightly different schedules. For example, USPSTF lists stool DNA-FIT every 1–3 years, while ACS 2026 lists multi-target stool DNA every 3 years. Colonoscopy every 10 years, annual FIT, CT colonography every 5 years, and sigmoidoscopy every 5 years are common major-guideline strategies for average-risk screening.
Practical rule: Follow the interval associated with the specific test your clinician ordered and the guideline your care team uses. A prior abnormal test, inadequate bowel prep, polyp history, or higher-risk condition can change the schedule.
Evidence
Primary sources for this page
American Cancer Society2026 colorectal cancer screening recommendationsUSPSTFRecommended screening strategies and intervalsCDCScreening overview and follow-up principle
Medical content reviewed against these sources on September 5, 2026. This does not replace clinician review before public launch.