Preventive-to-diagnostic guide
Medicare Screening Follow-Up Costs
A no-cost screening can lead to diagnostic imaging, pathology, procedures or office visits with Part B cost sharing. Learn where Medicare draws the line.
The transition
Screening ends where evaluation begins
A screening looks for disease before symptoms are present. Once a test finds an abnormality, or a patient reports a sign or symptom, later imaging, laboratory work, biopsy or specialist evaluation is generally diagnostic. The Part B deductible and usually 20% coinsurance can apply under Original Medicare.
Mammography example
Screening and diagnostic mammograms have different cost rules
Screening mammogram
Medicare covers a baseline mammogram for eligible women ages 35–39 and a screening mammogram every 12 months for women 40 and older. There is no cost when the provider accepts assignment.
Diagnostic mammogram
When medically necessary to evaluate a symptom or abnormal result, Medicare can cover additional mammograms. After the Part B deductible, 20% coinsurance generally applies.
Colorectal exception
Follow-up colonoscopy can remain a screening benefit
A colonoscopy performed after a positive Medicare-covered noninvasive stool or blood-based screening test is covered as a screening colonoscopy. If a polyp or other tissue is found and removed during a screening colonoscopy, the Part B deductible does not apply, but 15% coinsurance can apply to the provider and facility services.
Ask about every component: gastroenterologist, facility, anesthesia and pathology billing can come from different entities. Confirm that each accepts assignment.
Office visit
Discussing an abnormal result can be a separate service
The clinician may bill an evaluation-and-management service when the encounter includes medically necessary work beyond the preventive service. Examples include assessing a breast lump, adjusting medication for high blood pressure found at a visit or investigating symptoms disclosed during a wellness appointment.
Estimate the full episode
Questions that reduce billing surprises
- Is the first test preventive for my age, risk and timing?
- What happens if the result is abnormal?
- Which follow-up services are likely to be diagnostic?
- Are the facility, clinician, radiologist, anesthesiologist and pathologist participating?
- What network and authorization rules apply under my Medicare Advantage plan?
- Will I receive an Advance Beneficiary Notice if Original Medicare may not pay?
Frequently asked questions
Screening Follow-Up Costs Questions
Does a no-cost screening make every related service free?
No. Diagnostic evaluation, treatment, office services, pathology and other components can have their own Medicare coverage and cost rules.
Is a mammogram after a lump is found preventive?
It is generally diagnostic because it evaluates a symptom or finding. The Part B deductible and coinsurance can apply.
Is colonoscopy after a positive stool test still screening?
Yes, when it follows a positive Medicare-covered noninvasive colorectal screening test. Special cost rules still apply if tissue is removed.
Why did I receive several bills for one procedure?
A facility, clinician, anesthesia provider, radiologist and pathology laboratory can submit separate claims. Review each claim on the Medicare Summary Notice or plan EOB.
Primary references
Official Sources
- Medicare.gov: Preventive and screening services
- Medicare.gov: Mammograms
- Medicare.gov: Colonoscopies
- Medicare.gov: Medicare Summary Notice
Reviewed against official sources on August 22, 2026. Medicare and state program rules can change; verify current requirements before acting.
Independent Medicare guidance
Make the Next Decision With the Actual Details in Front of You
Benjamin Thompson can help compare the Medicare insurance options represented by Thompson Medicare Brokerage using your doctors, prescriptions, coverage priorities and budget.
Thompson Medicare Brokerage is not connected with or endorsed by the U.S. government or the federal Medicare program. This page provides general educational information. Coverage, costs, eligibility, networks, formularies and enrollment rights depend on individual facts, location, plan and coverage year. Thompson Medicare Brokerage does not offer every plan available in every area; Medicare.gov, 1-800-MEDICARE and SHIP can provide information about all available options.