Medicare Lung Cancer Screening (LDCT): Free Annual CT Scan (2025)

Lung cancer is the leading cause of cancer death in the United States, killing more people than breast, colon, and prostate cancer combined. The good news: Medicare covers annual low-dose CT (LDCT) lung cancer screening at $0 for eligible current and former smokers — a test that reduces lung cancer mortality by 20% in high-risk populations.

Lung Cancer Screening Coverage at a Glance

Who Is Eligible for Free Lung Cancer Screening?

Medicare updated its lung cancer screening eligibility criteria in 2022, expanding coverage to a larger population of high-risk beneficiaries. The previous criteria (ages 55–77) were replaced with the following:

All Four Criteria Must Be Met

• Age 50 to 77 at the time of screening
• Smoking history of 20 pack-years or more — A "pack-year" equals one pack of cigarettes per day for one year. So 20 pack-years means: 1 pack/day for 20 years, OR 2 packs/day for 10 years, OR any combination that totals 20. Your doctor will help calculate this.
• Current smoker OR former smoker who quit within the past 15 years — You do not have to still be smoking to qualify; people who quit recently remain at elevated risk.
• Asymptomatic — No current signs or symptoms of lung cancer (such as unexplained cough, hemoptysis, or chest pain). If you have symptoms, you need a diagnostic workup, not a screening test.

A written order from a physician, nurse practitioner, or physician assistant is also required. Your primary care provider can provide this order at your annual wellness visit or any routine appointment.

The Shared Decision-Making Visit: Required Before Your First Scan

Before your first LDCT lung screening, Medicare requires a separate shared decision-making counseling visit with your provider. This visit is covered at $0 and serves several purposes:

• Discuss the potential benefits of screening — early detection, reduced lung cancer mortality
• Discuss the potential harms — false positives, anxiety, unnecessary follow-up procedures, radiation exposure (though low with LDCT)
• Review what happens if something is found and what follow-up might look like
• Discuss smoking cessation resources if you are a current smoker
• Confirm that you meet eligibility criteria and are an appropriate candidate for screening

This visit is not required for your second or subsequent annual screenings — only the first one. It can be conducted in person or, in many cases, via telehealth.

Smoking Cessation Counseling: Free and Included

Medicare covers smoking cessation counseling at $0 — up to 8 individual or group sessions per year. This counseling must be offered at the shared decision-making visit if you are a current smoker. It can also be accessed independently through your primary care provider at any time.

Smoking cessation is the single most important thing a current smoker can do to reduce lung cancer risk — even more impactful than the screening itself. Medicare's coverage of both screening and cessation counseling together reflects this dual strategy.

Note that prescription smoking cessation medications (varenicline/Chantix, bupropion/Zyban, nicotine replacement) are covered under Part D. Nicotine replacement products are covered when prescribed by a provider.

What the Scan Involves

A low-dose CT (LDCT) scan of the chest is a quick, painless procedure:

• Duration: Approximately 10–15 minutes from check-in to completion; the scan itself takes less than 2 minutes
• Radiation: Low-dose — uses significantly less radiation than a standard diagnostic chest CT; roughly equivalent to a few months of natural background radiation
• No contrast dye: Unlike many CT scans, LDCT lung screening does not require intravenous contrast injection
• Preparation: No special preparation — no fasting, no medication changes needed
• What happens: You lie on a table that moves through a donut-shaped scanner; a technician will ask you to hold your breath briefly (typically 5–10 seconds) while images are captured
• Results: A radiologist reads the images and reports results to your ordering physician, typically within a few days

Understanding Your Results: The Lung-RADS System

Lung cancer screening results are reported using the Lung-RADS classification system, developed by the American College of Radiology. Results are categorized from 1 to 4:

• Lung-RADS 1 (Negative): No nodules, or clearly benign findings. Recommendation: Continue annual screening.
• Lung-RADS 2 (Benign appearance): Nodule present but has features strongly suggesting it is benign. Recommendation: Continue annual screening.
• Lung-RADS 3 (Probably benign): Nodule with low probability of malignancy (<5%). Recommendation: Short-interval follow-up CT in 6 months.
• Lung-RADS 4A/4B (Suspicious): Nodule with moderate to high suspicion for malignancy. Recommendation: Additional imaging (PET scan), possible biopsy, or surgical evaluation depending on sub-category.
• Lung-RADS 4X (Very suspicious): Nodule with very high suspicion; additional features further increase concern. Prompt workup required.

The majority of people screened will have Lung-RADS 1 or 2 results — no findings of concern. A Lung-RADS 3 or higher result does not mean you have cancer; it means your doctor needs more information. False positives are one of the known limitations of lung cancer screening, which is why the shared decision-making visit covers this topic in advance.

Follow-Up Coverage: When a Nodule Is Found

Here is an important cost distinction that surprises many beneficiaries: the annual screening LDCT itself is free ($0). However, if that screening finds something that requires further investigation, subsequent imaging or procedures are billed as diagnostic, not preventive — and your standard Part B cost-sharing applies.

This means:

• A 6-month follow-up CT scan for a Lung-RADS 3 nodule: 20% coinsurance after the $257 Part B deductible
• A PET scan to characterize an indeterminate nodule: 20% after deductible
• A bronchoscopy or CT-guided biopsy: 20% after deductible
• Surgical intervention (if cancer is confirmed): Part A hospital deductible of $1,676 per benefit period

This cost structure is important to know in advance but should not discourage you from getting screened. The potential benefit — catching lung cancer at Stage I or II, when it is far more treatable — far outweighs the risk of out-of-pocket costs for follow-up. Medigap plans cover the 20% coinsurance, making follow-up procedures cost-free for Medigap enrollees.

If Lung Cancer Is Found: Treatment Coverage

If screening leads to a lung cancer diagnosis, Medicare covers the full spectrum of treatment. Depending on the stage and type of lung cancer, this may include:

• Surgery: Lobectomy, segmentectomy, or VATS (video-assisted thoracoscopic surgery) — covered under Part A
• Radiation therapy: Including stereotactic body radiation therapy (SBRT) for early-stage or inoperable cases — covered under Part B
• Chemotherapy: Covered under Part B (IV infusion) or Part D (oral chemotherapy agents)
• Targeted therapy: For tumors with actionable mutations (EGFR, ALK, ROS1, KRAS, etc.) — covered Part D or Part B depending on administration route
• Immunotherapy: PD-1/PD-L1 inhibitors (pembrolizumab, nivolumab, atezolizumab) — covered Part B as infused medications

For a full overview of Medicare's cancer treatment coverage, see our Medicare Cancer Coverage guide.

Medicare Advantage and Lung Cancer Screening

Medicare Advantage (Part C) plans are required by law to cover all ACA-mandated preventive services, including LDCT lung cancer screening, at $0 — the same as Original Medicare. If your Medicare Advantage plan charges you a copay for this screening, that is incorrect; contact your plan or your State Health Insurance Assistance Program (SHIP) for assistance.

Why This Screening Saves Lives: The Evidence

The National Lung Screening Trial (NLST), involving over 53,000 participants, demonstrated a 20% relative reduction in lung cancer mortality among high-risk smokers who received annual LDCT compared to chest X-ray. The subsequent NELSON trial found even larger reductions — up to 24% in men and a striking 33% in women — using a similar LDCT protocol. These results drove the 2022 expansion of Medicare's eligibility criteria to include more beneficiaries at younger ages and lower smoking thresholds.

Lung cancer caught at Stage I has a 5-year survival rate of approximately 60–90%, compared to less than 10% for Stage IV disease. Annual screening is the only proven method for catching lung cancer before it produces symptoms — by which point it has typically already spread.

Frequently Asked Questions