Medicare Cancer Screenings: Free Preventive Tests (2025)

Medicare covers a wide range of cancer screenings at $0 cost-sharing — but only when they are billed as preventive services under the right conditions. Understanding the difference between preventive and diagnostic billing, which exams qualify, and how to avoid surprise charges can save you hundreds of dollars and ensure you get the early detection care Medicare intends to provide.

Medicare Cancer Screenings: Quick Reference

The Preventive vs. Diagnostic Billing Trap

This is the single most important concept for Medicare beneficiaries to understand before any screening procedure. Medicare bills services in two categories: preventive (no cost-sharing) and diagnostic (subject to Part B deductible and 20% coinsurance). The trap occurs when a visit starts as preventive but converts to diagnostic during the procedure.

The Colonoscopy Polyp Conversion Problem

A screening colonoscopy for an average-risk individual costs $0 under Medicare Part B — there is no deductible and no coinsurance. However, if the physician finds and removes a polyp during that same procedure, Medicare reclassifies the encounter. The facility fee and anesthesia may still be billed at the preventive $0 rate, but the polyp removal itself is billed as a therapeutic/diagnostic procedure, and you can owe 20% coinsurance on that portion.

This is not a mistake or a billing error — it is how Medicare's rules work. CMS has acknowledged the issue repeatedly but full legislative resolution has been partial. The Consolidated Appropriations Act of 2023 began phasing in protections so that colorectal cancer screening colonoscopies would not trigger cost-sharing even when a polyp is removed; however, the phase-in is gradual and in 2025 beneficiaries may still owe a reduced (but not zero) coinsurance amount in some circumstances. Ask your provider and plan about current cost-sharing before your procedure.

The Diagnostic Mammogram Distinction

A screening mammogram — a routine bilateral mammogram ordered for a woman with no current symptoms — is covered at $0 annually for women 40 and older. If the radiologist identifies an area of concern and orders additional imaging, or if you have a known breast lump or symptoms, the next mammogram is classified as a diagnostic mammogram. A diagnostic mammogram is subject to the Part B deductible and 20% coinsurance. The same physical procedure, billed differently, produces very different costs. Similarly, if a biopsy is required, that procedure carries diagnostic billing.

The FOBT/FIT Follow-Up Trap

A fecal occult blood test (FOBT) or fecal immunochemical test (FIT) ordered as a routine annual screening is $0 under Part B. If that test comes back positive and you need a follow-up colonoscopy to investigate, Medicare treats that follow-up colonoscopy as a diagnostic colonoscopy, not a preventive screening — because there is now a clinical reason to investigate. You would then owe the Part B deductible and 20% coinsurance on the diagnostic colonoscopy. Plan for this possibility if you use stool-based testing.

The Annual Wellness Visit vs. "Getting a Physical": A Critical Distinction

Medicare covers two types of wellness visits for most beneficiaries:

• Welcome to Medicare Visit (IPPE — Initial Preventive Physical Examination): Covered once in your lifetime, within the first 12 months of your Medicare Part B enrollment. This includes a review of your medical and social history, a measurement of height, weight, blood pressure, and BMI, a simple vision test, a review of your potential risk factors for depression and other mental health conditions, education and counseling about preventive services and referrals, and an electrocardiogram (EKG) if you are male. This is not a full physical.
• Annual Wellness Visit (AWV): Covered at $0 once every 12 months after your first 12 months of Part B enrollment. The AWV includes a health risk assessment questionnaire, a review of your medical history, a list of current medications, a review of your functional ability and safety (fall risk, cognition screening), blood pressure measurement, and a personalized prevention plan. The AWV does not include a head-to-toe physical examination, bloodwork, or laboratory tests. Any additional services ordered at the same visit — labs, tests, specialist referrals — are billed separately and subject to normal cost-sharing.

What Medicare does not cover: A routine annual physical examination. If your doctor performs a comprehensive physical exam — listening to your heart and lungs, palpating your abdomen, ordering a full metabolic panel, checking reflexes, and providing a general health assessment — that is not a covered Medicare benefit under Original Medicare. You will be billed for it as an office visit, typically at 20% coinsurance after the Part B deductible.

The Wellness Visit Billing Trap

A common scenario: You schedule your "free annual physical" with your primary care doctor. Your doctor conducts what is documented as the AWV but also discusses a new symptom — say, knee pain or a skin lesion. The physician now has a documented medical complaint, which means the visit may be dual-billed: part of it as the AWV (preventive, $0) and part of it as an evaluation and management (E&M) office visit (diagnostic, subject to deductible and coinsurance). This is legal and appropriate billing, but many beneficiaries are surprised when they receive a bill. To avoid this, schedule separate visits for wellness and for new medical concerns when possible.

Mammograms: What Medicare Covers

Medicare Part B covers screening mammograms at $0 with the following parameters:

• One baseline mammogram for women ages 35–39 (covered once, not annually)
• One screening mammogram per year (every 12 months) for women age 40 and older
• No deductible, no coinsurance for the screening mammogram itself

3D mammography (digital breast tomosynthesis) is covered by Medicare when performed at the same time as a standard digital screening mammogram. If your provider offers only 3D mammography, Medicare covers it at the same $0 rate for eligible beneficiaries.

If the radiologist identifies an abnormality and you return for a diagnostic mammogram, additional views, or ultrasound, those services are billed under Part B at the normal cost-sharing rate. Your Part B deductible ($257 in 2025) applies, and you then owe 20% of the Medicare-approved amount.

Colorectal Cancer Screenings: Multiple Options

Medicare covers several types of colorectal cancer screenings. Different tests carry different schedules and risk profiles. Your physician can help you choose the right approach based on your age, health history, and risk factors.

• Colonoscopy (average risk): $0 every 10 years for people age 45+ who are not at high risk. If a polyp is found and removed, partial cost-sharing may apply (see billing trap section above).
• Colonoscopy (high risk): $0 every 2 years for people with a personal or family history of colorectal polyps or cancer, certain hereditary syndromes (Lynch syndrome, FAP), or other high-risk conditions.
• Stool DNA test (Cologuard): $0 every 3 years for average-risk adults age 45 and older. If the test is positive, a follow-up colonoscopy is ordered — and that colonoscopy is billed as diagnostic, not preventive.
• Fecal occult blood test (FOBT) / Fecal immunochemical test (FIT): $0 annually. Home-based stool test. Positive result requires diagnostic follow-up.
• Flexible sigmoidoscopy: $0 every 48 months, or every 24 months when used in combination with an annual FOBT.
• Barium enema: $0 every 48 months (average risk) or every 24 months (high risk); used as an alternative to sigmoidoscopy when other methods are not appropriate.

Lung Cancer Screening: Low-Dose CT (LDCT)

Medicare covers annual low-dose CT (LDCT) lung cancer screening at $0 for beneficiaries who meet all of the following criteria:

• Age 50 to 77
• A smoking history of at least 20 pack-years (one pack per day for 20 years, or two packs per day for 10 years, etc.)
• Currently smoke, OR quit within the past 15 years
• No signs or symptoms of lung cancer (this is a screening, not a diagnostic scan)
• Received a written order from your physician following a shared decision-making counseling session

The shared decision-making requirement: Unlike most Medicare preventive services, LDCT lung screening has a mandatory pre-screening counseling requirement. Your physician must document a shared decision-making visit discussing the benefits and harms of screening, the importance of smoking cessation, and the screening process. This visit must occur before the LDCT order is written. The counseling visit itself is billed separately; when ordered correctly as part of the LDCT benefit, the counseling is also covered at $0.

If the LDCT reveals a finding that requires a follow-up scan or biopsy, those subsequent procedures are billed as diagnostic under Part B with standard cost-sharing.

Cervical and Pelvic Cancer Screenings

Medicare Part B covers cervical and pelvic cancer screening for women as follows:

• Pap smear: $0 every 24 months for all women with Medicare Part B. If you are at high risk for cervical or vaginal cancer, or are of childbearing age and had an abnormal Pap smear in the past 36 months, you qualify for an annual ($0) Pap smear.
• HPV test (co-testing): Covered at $0 as part of the cervical cancer screening benefit when performed with the Pap smear, following the same frequency schedule.
• Pelvic examination: $0 every 24 months, or annually for high-risk women. The pelvic exam is performed by your doctor and includes a clinical breast exam.

High-risk factors that qualify you for more frequent screening include: early onset of sexual activity, multiple sexual partners, history of STIs, or other documented risk factors for cervical cancer.

Prostate Cancer Screening (PSA Test)

Medicare covers the PSA (prostate-specific antigen) blood test at $0 annually for men age 50 and older. This is a straightforward blood draw — no additional cost-sharing beyond the $0 preventive coverage. The digital rectal exam (DRE) performed in conjunction with PSA screening is also covered at $0 as part of the same prostate cancer screening benefit.

Note that PSA screening is a topic of ongoing discussion in clinical medicine — the U.S. Preventive Services Task Force (USPSTF) recommends individualized decision-making for men ages 55–69 and does not recommend PSA screening for men 70 and older. However, Medicare's coverage rule is age 50+, and your physician can discuss whether screening makes sense for your individual situation.

Other Key Preventive Screenings Medicare Covers

Hepatitis C Screening

Medicare covers hepatitis C virus (HCV) screening at $0 for:

• Adults born between January 1, 1945, and December 31, 1965 — once per lifetime
• Adults at high risk for HCV infection — as frequently as annually

High-risk individuals include those with a history of injection drug use, certain blood transfusions before 1992, or other documented risk factors. Hepatitis C is highly treatable today — early detection through screening leads to curative treatment that also reduces liver cancer risk significantly.

Cardiovascular and Lipid Screening

Medicare covers cardiovascular disease risk screening at $0 once every 5 years. This includes tests for total cholesterol, LDL, HDL, and triglycerides. No deductible applies. This screening is available to all Medicare Part B beneficiaries with no additional risk criteria required.

Diabetes Screening

Diabetes screening tests (fasting glucose and HbA1c) are covered at $0 up to twice per year for beneficiaries with any of the following risk factors: overweight, hypertension, dyslipidemia, obesity, or a family history of diabetes. Early detection of prediabetes or diabetes allows intervention before complications develop — including complications that increase cancer risk.

Abdominal Aortic Aneurysm Ultrasound

Medicare covers a one-time ultrasound screening for abdominal aortic aneurysm (AAA) at $0 for men who have smoked at least 100 cigarettes in their lifetime. This screening must occur within the first 12 months of your Medicare Part B enrollment. It is typically referred during the Welcome to Medicare visit. Missing this window means losing the benefit — there is no second opportunity under the current coverage rules.

HIV Screening

Medicare covers HIV screening at $0 annually for beneficiaries at increased risk, and once for all adults between ages 15 and 65 who request it. High-risk factors include current or past injection drug use, multiple sexual partners, a sexual partner who is HIV positive, or other documented risk factors.

Bone Density Scan (DEXA)

While not a cancer screening, Medicare's bone density coverage at $0 every 24 months is included here because it is a Part B preventive benefit that many beneficiaries miss. Women age 65 and older are considered at standard risk for osteoporosis; women under 65 and men who have documented risk factors (steroid use, hyperparathyroidism, recent fracture, etc.) also qualify. See our full Osteoporosis Coverage Guide for details.

What Medicare Does NOT Cover for Cancer Screenings

• Routine annual physical examination: Medicare does not cover a traditional comprehensive physical exam. The AWV is not a physical. If your provider performs a physical beyond the AWV's scope, you will receive a bill.
• Genetic testing (BRCA, Lynch syndrome): Medicare may cover genetic counseling and testing when there is a documented personal or strong family history justifying the test, but routine genetic cancer risk screening panels are not a standard covered preventive benefit. Coverage depends on medical necessity documentation.
• CT colonoscopy (virtual colonoscopy): CMS has not finalized coverage of CT colonography (CTC) as a colorectal cancer screening benefit under Medicare as of 2025. It is generally not covered as a preventive screening, though some Medicare Advantage plans may cover it.
• Skin cancer screening: Routine skin cancer screening by a dermatologist is not a covered Medicare preventive benefit. If you have a suspicious lesion examined and biopsied, that is a diagnostic service and billed under Part B with cost-sharing.
• Diagnostic follow-up from positive screenings: Any diagnostic procedure that results from a positive preventive screening carries normal Part B cost-sharing (deductible + 20%).

How to Avoid Surprise Bills from Preventive Screenings

1. Confirm the billing code before your appointment. Ask the scheduling staff: "Will this be billed as a preventive screening (no cost-sharing) or as a diagnostic procedure?" For colonoscopy, ask specifically: "If a polyp is found and removed, how will you bill that portion?"
2. Schedule wellness and medical concerns separately. If you bring up a new symptom at your Annual Wellness Visit, the provider may legitimately bill an E&M code in addition to the AWV, resulting in cost-sharing. Keep your AWV focused on preventive planning and schedule a separate visit for medical issues.
3. Know your plan's policies. Medicare Advantage plans may have different cost-sharing rules for screenings, and some are more generous than Original Medicare. Review your Evidence of Coverage (EOC) annually.
4. Consider Medigap Plan G or Plan N. These supplemental plans cover Part B coinsurance (20%) and can protect you when a preventive visit converts to diagnostic billing, when a biopsy is needed, or when multiple services are billed at the same visit.
5. Appeal unexpected bills. If you receive a bill for a screening you believe should have been preventive, you have the right to appeal. The first step is to contact your provider and request a review of how the service was billed. If it was coded as diagnostic when it should have been preventive, the provider may be able to correct the billing.
6. Use Medicare's "What's covered" tool. The official tool at medicare.gov/coverage lets you search any service to verify coverage before your appointment.

Frequently Asked Questions