Table of Contents
Many individuals enrolled in both Medicaid and Medicare (“dually eligible individuals”) are eligible for assistance with Medicare out-of-pockets costs. Thus, any health care bills they receive should raise a red flag that they are being improperly billed or have lost their financial assistance. This issue brief describes the different types of health care bills a Medicare enrollee might receive, explains how health care bills are covered, and provides information on assistance available and advocacy tips for how to address issues that may arise.
For additional state protections for medical billing, see our chart, State Medical Billing Protections for Dually Eligible Individuals. Also see our companion issue brief Medicare Premium Bills and Dually Eligible Individuals for information about additional financial assistance with Medicare premiums costs.
Cost-Sharing Bills
“Cost-sharing” is an umbrella term for costs associated with health care services where Medicare pays for some, but not all, of the care. Types of cost-sharing include:
- Deductibles, where an enrollee has to pay a certain amount before coverage kicks in.
- Co-pays, where an enrollee has to pay a certain dollar amount for a service.
- Co-insurance, where an enrollee has to pay a certain percentage of the service cost.
For people with Original Medicare, the Medicare.gov website and Medicare and You Handbook both describe what cost-sharing to expect for services and items. For people with Medicare Advantage, each plan’s Explanation of Coverage documents describe the cost-sharing expected for services and items. Part D plans describe cost-sharing for prescription drugs in plan coverage documents and on Medicare Plan Finder. Cost-sharing often shows up as a request to pay at the provider’s office or pharmacy counter, or a bill sent afterwards.
In addition to the bill, Medicare enrollees should receive summaries of care received and related cost-sharing from either Medicare or their Part D or Medicare Advantage plan. Individuals in Original Medicare can check their online Medicare account for the Medicare Summary Notice, which describes services received and cost-sharing charged for Parts A and B services. For more information on interpreting notices, see CMS’s Part A Medicare Summary Notice sample, Part B Medicare Summary Notice sample, Durable Medical Equipment Medicare Summary Notice sample; and Senior Medicare Patrol’s primer on how to read Medicare statements.
Part D enrollees should receive an Explanation of Benefits statement that describes Part D medications provided and cost-sharing charged. Individuals in Medicare Advantage should receive an Explanation of Benefits document for services and items received and cost-sharing charged from their plan.
Bills for Care Not Covered by Medicare
When a provider bills an individual for the full cost of a service or item, this is an indication that either the provider is not billing Medicare properly, or that the care may not be covered. If the provider submitted a claim that was denied coverage (either to a Medicare Advantage plan or Original Medicare), the Medicare enrollee should receive a notice explaining the denial and opportunities for appeal.
For individuals in Original Medicare, if the provider declined to submit a claim because they believe it is for a non-covered service, the provider should have let the Medicare enrollee know in writing with an Advance Beneficiary Notice before the service was rendered.[1]
Medicare Advantage plans must respond to requests from enrollees and their providers about whether the plan will cover an upcoming service, item, or Part B medication – this is called an organizational determination. The plan’s coverage decision must be in writing and must include whether the plan will cover care, how much the enrollee will need to pay, and notify the enrollee of their right to appeal the decision.[2]
For both Original Medicare and Medicare Advantage enrollees, Part D medications are covered based on the plan’s formulary. Individuals and their providers can check the plan’s formulary by looking at plan documents, visiting Medicare Plan Finder, or calling the plan.
Assistance Available to Cover Health Care Bills
Assistance with health care bills is available through a variety of Medicaid and Medicare programs.
Type of Bill | What to screen for |
Medicare cost-sharing |
|
Service not covered by Medicare |
Full Medicaid
Full Medicaid refers to coverage for Medicaid services. A person with Medicare may be dually eligible for full Medicaid, which can be important for accessing services Medicare does not cover, such as long-term care, non-emergency medical transportation, and dental, vision, and hearing services. Full Medicaid can also cover cost-sharing charges for services covered by Medicare.
Qualified Medicare Beneficiary (QMB)
QMB is a type of Medicare Savings Program. Medicare Savings Programs are Medicaid programs that help low-income individuals with Medicare costs. A QMB enrollee cannot be billed for Medicare Part A or Part B related cost-sharing.[3] QMB enrollees also receive the Part D LIS (see below). A person can be on full Medicaid and QMB at the same time.
QMB enrollment is recommended for individuals on full Medicaid because it offers more comprehensive premium and cost-sharing coverage and has more robust federal protections from improper billing. [4] QMB eligibility varies by state. An individual can check their QMB status by reviewing their Medicare Summary Notice, calling 1-800 Medicare, or contacting their state Medicaid program.
FIDE SNPs
Fully Integrated Dual Eligible (FIDE) SNPs are a type of Medicare Advantage plan designed specifically for people dually eligible for Medicare and Medicaid. FIDE SNPs have the highest federal requirements for integration among Medicare Advantage plans. Twelve states currently have FIDE SNPs in their market, and often availability is restricted to a few counties in the state.[5]
FIDE SNPs are required to cover Medicare cost-sharing (co-pays, co-insurance, and deductibles) for all enrollees, as of January 2025.[6] Note that another D-SNP type, the Coordination Only Dual Eligible Special Needs Plan (CO D-SNP) that is an Applicable Integrated Plan (AIP) is also required to cover Medicare cost-sharing.[7] Currently, CO D-SNP AIPs only exist in California.[8] To determine if a plan is a FIDE SNP or a CO D-SNP that is an AIP, search the plan ID in this CMS SNP data report.
LIS helps with Part D premiums and cost-sharing. Individuals who are on Medicaid or a Medicare Savings Program should be auto-enrolled into LIS. Individuals can also apply for LIS at the Social Security Administration, as it has higher eligibility limits than most Medicaid programs. Please note that dually eligible individuals receiving Home- and Community-Based Services and dually eligible individuals residing in nursing facilities should have zero cost-sharing for Part D prescription drugs when enrolled in LIS.
When a State Requires a Person to Apply to Medicare
In addition to the assistance programs listed above, if the individual’s state Medicaid program required them to apply for Medicare as a condition for Medicaid eligibility, then according to CMS policy the state should pay for the individual’s premiums and cost-sharing.[9] Fourteen states appear to have policies that require Medicare-eligible individuals to apply to Medicare as a condition of Medicaid eligibility.[10]
Other Programs
This brief is not a comprehensive list of all programs that may help with Medicare costs. If the individual is not eligible for these programs, advocates may also want to screen for other assistance such as hospital charity care[11], state and local programs (including State Pharmaceutical Assistance Programs (SPAPs) and other supplemental coverage (e.g., Medigap and coverage provided to employees, retirees, or veterans).
When Dual Eligible Enrollees Are Improperly Charged for Part A or B Services
Health care providers are prohibited from billing QMB enrollees for Medicare cost-sharing for Medicare Part A or B services and items, and are generally not allowed to bill non-QMB enrollees who are on full Medicaid.[12] State billing protection laws offer additional safeguards for dually eligible individuals. See Justice in Aging’s chart of State Medical Billing Protections for Dually Eligible Individuals.
To respond to an incorrect cost-sharing bill, first raise the issue with the provider’s office. The Justice in Aging Improper Billing Toolkit includes template letters for notifying providers.
If the person is enrolled in Original Medicare, and contacting the provider’s office does not resolve the issue, the next step is to call 1-800 Medicare and request assistance with dealing with an improper billing issue. Indicate that it is an improper billing case and note (when applicable) that the Medicare enrollee is on QMB and that your client has tried but been unable to resolve this issue with the provider. Medicare has a process in place to notify providers of their improper billing obligations.
If the person is enrolled in a Medicare Advantage plan, a next step after trying to resolve the issue with the provider is to contact the plan. Medicare Advantage plans have an obligation to ensure that enrollees are not charged for a service that the plan should have covered, even if the provider did not follow plan rules in the billing process.[13]
If the plan fails to timely resolve the issue, the next step is to contact 1-800 Medicare. Indicate that it is an improper billing case and note (when applicable) that the Medicare enrollee is on QMB.[14] Medicare can also assist with filing customer service-related complaints if plans failed to provide assistance with improper billing issues.
When LIS Enrollees Are Improperly Billed for Prescription Medication
Issues can occur if plans do not have the enrollee’s LIS status properly documented. Individuals enrolled in LIS who are charged more than the LIS cost-sharing should follow-up directly with the plan customer service number and request that the plan representative update the system. Pharmacists can also help to begin this process at the point-of-sale by sending the plan proof of the individual’s LIS status, also known as best available evidence.
Examples
CMS Sends a Letter to a Provider to Stop Improper Billing
Glenn is enrolled in QMB and Original Medicare but was billed a co-pay after her doctor’s office visit for Medicare-covered services. Glenn called the doctor’s billing department, but they insisted on charging her a co-pay. Glenn’s advocate called 1-800-Medicare with Glenn and let them know that this was a case of QMB improper billing.
The representative at 1-800 Medicare referred the case to Glenn’s Medicare Administrative Contractor, who sent a letter to the provider alerting them to their obligations. The letter included the language, “Promptly review your records for efforts to collect Medicare cost-sharing from Glenn Smith, refund any amounts already paid, and recall any past or existing billing (including referrals to collection agencies) for Medicare-covered items and services.”[15]
The provider stopped billing Glenn, but Glenn’s advocate was concerned that the provider would bill others. Her advocate alerted the Senior Medicare Patrol in her state that the provider was improperly billing QMB enrollees. She also reached out to her state’s Medicaid agency to report the issue.
A Medicare Advantage Plan’s Obligation to Stop Improper Billing
Maria is enrolled in QMB and a Medicare Advantage plan. Her provider billed her for a $35 copay. When she received the bill, she contacted the doctor’s billing department and expressed confusion as she had never been billed before. They stated that this was the correct copay that she had to pay before her next visit or they would cancel the upcoming appointment.
Maria’s advocate called Maria’s plan to explain the situation. At first, the plan representative said it should be an issue that Maria resolves directly with the provider. The advocate reminded the plan representative that the plan has an obligation to ensure that network providers are not charging QMB enrollees.[16] The plan representative contacted the provider’s office to inform them that Maria had QMB and could not be billed any cost sharing after the plan paid.
Conclusion
Though most dually eligible individuals should receive help with health care costs, there are many opportunities for things to go wrong. Justice in Aging is interested in hearing about situations where individuals are receiving incorrect or improper premium or cost-sharing bills; please let us know by emailing info@justiceinaging.org.
Endnotes
See pages 65 and 66 of Medicare and You 2026 and Section 50 of Chapter 30 of the CMS Medicare Claims Processing Manual. For the ABN form and instructions, see CMS, FFS ABN. For information about how providers should handle the ABN process for dually eligible individuals, see Question 16 of CMS, Qualified Medicare Beneficiary Program, FAQ on Billing Requirements (July 2018). ↑
Pages 65, 66 and 102 of Medicare and You 2026. See Section 40.4, Parts C and D Enrollee Grievance, Organization/Coverage Determinations and Appeals Guidance (Nov. 2024). ↑
CMS, Prohibition on Billing Qualified Medicare Beneficiaries (Sept. 2025). ↑
In many cases, the state should be auto-enrolling full Medicaid enrollees into QMB. See, e.g., 42 C.F.R. 435.909 (for the obligation of states to auto-enroll into QMB individuals who are in SSI-based Medicaid) and Section 1.4.4 of Chapter 1 of the CMS Manual State Payment of Medicare Premiums (for the state’s obligation to screen for assistance when a Medicaid enrollee becomes eligible for Medicare). ↑
Arizona, California, Florida, Hawaii, Idaho, Massachusetts, Minnesota, New Jersey, New York, Tennessee, Virginia, Wisconsin all have FIDE SNPs as of May 2026. CMS, SNP Data (May 2026). ↑
Integrated Care Resource Center (ICRC), Spotlight: Changing Definitions of Different D-SNP Types in 2025 (September 27, 2024). ↑
42 C.F.R. § 422.561. ↑
Author analysis of CMS SNP data. ↑
Section 1.9 of the CMS Medicare Manual State Payment of Medicare Premiums (”…under CMS policy, states cannot require Medicaid applicants and beneficiaries to apply for Medicare as a condition of eligibility unless the state pays any Medicare cost-sharing or premiums the individual incurs.”). ↑
Alaska, California, Colorado, Idaho, Florida, Maryland, Massachusetts, Michigan, Mississippi, New York, Utah, Virginia, Washington State, and West Virginia. ↑
Hospitals are often required to provide patient financial assistance as part of their non-profit status. ↑
For more information, see Section 3 of CMS, Provider Enrollment and Third-Party Liability for Items and Services Rendered to Dually Eligible Individuals (Jan. 2025). ↑
See CMS, Letter to plans re. Contract Year 2026 Readiness Checklist for Medicare Advantage Organizations, Prescription Drug Plan Sponsors, 1876 Cost Plans and Programs for All Inclusive Care for the Elderly (Nov. 4, 2025). See also CMS, Memo to Medicare Advantage Organizations re. Reminder of Prohibition on Billing Qualified Medicare Beneficiaries (QMBs) and Resources Available to Identify QMB Status (Oct. 31, 2024) (“Plans may be subject to compliance or enforcement actions if they do not ensure that all amounts incorrectly collected from Medicare enrollees either directly or through providers are refunded. This includes amounts incorrectly collected by providers from QMBs as a result of inaccurate information sent to the provider by the plan regarding an enrollee’s QMB status. Plans also must take action to ensure that their providers cease improper QMB billing or collection actions brought to the attention of the plan.”) ↑
See CMS’s One-Time Notification re. Issuing Compliance Letters to Specific Providers and Suppliers Regarding Inappropriate Billing of Qualified Medicare Beneficiaries (QMBs) for Medicare Cost-Sharing (Nov. 4, 2016). ↑
See a sample letter from CMS at CMS Manual System One Time Notification re. Issuing Compliance Letters to Specific Providers and Suppliers Regarding Inappropriate Billing of Qualified Medicare Beneficiaries (QMBs) for Medicare Cost-Sharing (Nov. 4, 2016). ↑
CMS, Memo to Medicare Advantage Organizations re. Reminder of Prohibition on Billing Qualified Medicare Beneficiaries (QMBs) and Resources Available to Identify QMB Status (Oct. 31, 2024). ↑
