A practice manager at a two-physician internal medicine office called us in June with a letter from her state Medicaid agency. A patient had complained. The practice had sent her three statements for a $25.60 coinsurance balance on a 99214 visit, then a fourth marked "final notice." The patient was a Qualified Medicare Beneficiary. Under federal law she owed nothing, the practice was not allowed to ask, and the collections letter was the problem, not the unpaid balance.
The manager was not careless. The billing system showed the Medicare remit with a $25.60 patient responsibility, the secondary Medicaid claim had paid zero, and the statement cycle did what statement cycles do. Nobody had read the remark code on the remit, and nobody had configured the system to treat this patient differently from any other Medicare patient with a secondary plan. This is the most common compliance gap we find in small practices, and it is almost never intentional.
This article covers the Qualified Medicare Beneficiary billing rules as they apply to an independent practice: what the program is, why the balance is not collectible, where the status is visible before and after the visit, how to post the remaining amount so it does not turn into a statement, and how to refund money that was collected by mistake.
Key takeaways
- A Qualified Medicare Beneficiary (QMB) is a Medicare patient whose state Medicaid program pays their Part B premium and Medicare cost sharing; federal law (Section 1902(n)(3)(B) of the Social Security Act) prohibits any Medicare provider from billing them for deductibles, coinsurance or copays.
- The prohibition applies whether or not the practice is enrolled with Medicaid, whether the patient is in Original Medicare or a Medicare Advantage plan, and whether or not Medicaid pays the crossover claim.
- Since July 2018, the Medicare remittance advice flags QMB patients with remark codes N781, N782 and N783, and the HETS eligibility response shows QMB status before the visit.
- Any amount collected from a QMB patient must be refunded, and a practice that keeps billing after being told risks sanctions.
- The fix is a workflow: check eligibility, flag the account, post the balance to a QMB adjustment code, and hold statements.
What the Qualified Medicare Beneficiary program is
QMB is one of the Medicare Savings Programs run by state Medicaid agencies. It covers Medicare patients with income at or below the federal poverty level and limited resources. The state pays the Part B premium and is responsible for the Medicare cost sharing (the deductible, the 20 percent coinsurance and any copays). Some QMB patients also qualify for full Medicaid benefits ("QMB Plus"); others have QMB only, which means Medicaid covers Medicare cost sharing but nothing else. For billing purposes the distinction does not matter: both groups are protected from cost-sharing bills.
The important word in the rule is "responsible." The state is responsible for the cost sharing, but most states pay it under a "lesser of" policy. If the Medicaid fee schedule rate for the service is lower than what Medicare already paid, the state pays nothing on the crossover claim. That is why the secondary claim in our opening example paid zero. Zero from Medicaid does not move the balance to the patient. It stays a provider write-off, and the practice has agreed to accept Medicare plus whatever Medicaid pays as payment in full by participating in Medicare at all.
CMS says this plainly in MLN article SE1128: providers who bill QMBs for cost sharing are violating their Medicare provider agreement and may be subject to sanctions. In practice the first contact is a patient complaint through 1-800-MEDICARE or the state Medicaid agency, followed by a letter like the one our client received.
Where QMB status shows up, before and after the visit
Practices that get this right check in two places. The first is the eligibility response. The Medicare HETS 270/271 transaction returns QMB status when the state has reported the patient to CMS, and most clearinghouse eligibility tools display it in the Medicare section of the response, often as a plan code or a note under "Medicaid" or "Other payer." If your front desk runs eligibility for every Medicare patient, this information is already coming back; the question is whether anyone looks at it and whether the system stores it on the account.
The second place is the Medicare remittance advice, the 835 electronic remit that reports what Medicare paid. Since July 1, 2018 (CMS change request 10433, which restored the QMB data that an earlier change had briefly removed), Medicare fee-for-service remits carry three alert remark codes for QMB patients:
| Remark code | What it says | What it means for posting |
|---|---|---|
| N781 | Alert: patient is a Medicaid/Qualified Medicare Beneficiary. Review your records for any wrongfully collected deductible. | The deductible amount on the remit is not patient responsibility; bill Medicaid as secondary, then write off what Medicaid does not pay. |
| N782 | Alert: patient is a Medicaid/Qualified Medicare Beneficiary. Review your records for any wrongfully collected coinsurance. | Same treatment for the coinsurance line. |
| N783 | Alert: patient is a Medicaid/Qualified Medicare Beneficiary. Review your records for any wrongfully collected copayment. | Same treatment for any copay. |
The remark codes sit beside the ordinary group and reason codes (PR-1 for deductible, PR-2 for coinsurance), and that is where systems go wrong. A payment posting engine reads PR-2 and moves $25.60 to patient responsibility. The N782 alert is text the poster may never see. If your posting is automated, ask your vendor whether the system can act on N781 to N783, and if it cannot, build a report that lists every remit line carrying those codes so a person can review it before statements go out.
Medicare Advantage remits do not use the CMS crossover process, but the same prohibition applies to their members. Most MA plans show a QMB or "dual" indicator in their portal eligibility screen. If an MA remit shows patient responsibility for a patient the state lists as QMB, treat it the same way: bill the state if you are enrolled, write off the rest, and do not send a statement.
A worked example: posting the 99214
Take the visit from the opening. The Medicare allowed amount for the 99214 is $128.00 in this example. Medicare pays 80 percent, $102.40, and reports $25.60 as coinsurance with PR-2 and N782 on the remit. The claim crosses over to the state Medicaid agency automatically because the patient is on file as QMB. The state's fee schedule rate for 99214 is $85.00. Under the lesser-of rule, the state compares its rate ($85.00) to what Medicare already paid ($102.40), finds Medicare paid more, and pays $0.00 on the crossover.
Correct posting looks like this: $102.40 posted as Medicare payment, $0.00 posted as Medicaid payment, and $25.60 posted to a dedicated adjustment code, something like "QMB cost-sharing adjustment." Patient balance: zero. The adjustment code matters because it lets you report how much QMB cost sharing you write off each year, and it keeps the amount out of bad debt and out of the contractual adjustment bucket where it would distort your payer analysis. If your system lacks a QMB code, ask for one; it is a five-minute configuration change.
What if the practice is not enrolled with Medicaid? Then the crossover claim will never be paid, and the outcome is the same: $25.60 to the QMB adjustment code, nothing to the patient. Being unenrolled does not create a right to bill the patient. For practices with many dual-eligible patients in states with higher Medicaid rates, enrolling for crossover payments is worth the paperwork; our credentialing team handles Medicaid enrollment as part of provider enrollment.
Refunding what was collected in error
When a practice discovers it collected from a QMB patient, the money goes back. There is no de minimis threshold in the rule and no offset against future visits without the patient's agreement. Our approach is to run a report of every payment posted to a patient account flagged QMB (or every account whose remits carried N781 to N783) for as far back as your records allow, then issue refunds by check or by reversing the card charge if the payment was recent. Document each refund with the date, amount, method and the reason "QMB cost sharing collected in error." If the patient has died or cannot be located, follow your state's unclaimed property process rather than keeping the funds; counsel can confirm the timeline.
The refund process is also the moment to stop the bleeding. Look at how the payment was collected. A copay taken at check-in means the front desk needs a QMB flag on the appointment screen. A statement payment means the statement run needs a hold. A collections payment means recalling the account and instructing the agency in writing. The Medicare Summary Notice tells patients they are QMB and should not be billed, so a patient who complains is usually quoting CMS, not guessing.
Building the workflow so it never reaches a statement
Every practice we have helped fix this problem ended up with the same five controls: eligibility on every Medicare patient at scheduling and at check-in, with the QMB indicator stored on the account; a patient class ("Medicare QMB") that drives a zero-copay rule; a posting review that catches N781 to N783 before balances move to patient responsibility; a statement hold on the QMB class; and an annual refund audit of payments on QMB accounts.
QMB status changes. Patients gain it when income falls and lose it when a state redetermination fails, which has happened often since Medicaid unwinding began in 2023. A patient who was QMB in January and lost it in April owes normal cost sharing from the date the state's coverage ended, and the eligibility response at each visit is the only way to know.
It also helps to write the rule into the patient financial policy in plain words: "If you are enrolled in the Qualified Medicare Beneficiary program, we will not bill you for Medicare deductibles, coinsurance or copays. Please tell us if you receive a statement." If your billing is outsourced, ask the vendor to show you their QMB report and refund log; our medical billing team reviews this in every payment posting cycle because the alternative is the letter our client received.
Questions we hear
The patient offered to pay the coinsurance. Can we accept it?
No. The prohibition is on the provider, not a waiver the patient can sign. A voluntary payment is still a payment for Medicare cost sharing, and CMS treats it the same as a billed one. Decline politely, explain that Medicare and Medicaid have the patient covered, and note the conversation in the account.
Can we bill a QMB patient for services Medicare does not cover?
The QMB protection covers Medicare cost sharing on Medicare-covered services. A service Medicare does not cover at all, such as a cosmetic procedure, is outside the rule, but Medicaid rules may still apply if the patient has full Medicaid, and you need an Advance Beneficiary Notice where one is required. In our experience most practices should treat these cases one at a time and ask counsel before collecting.
We are not enrolled with our state Medicaid program. Do we have to be?
Not to comply with the billing prohibition; that applies regardless. Enrollment only matters for receiving crossover payments. Several states offer a limited "QMB only" or cost-sharing enrollment that is simpler than full Medicaid enrollment. Whether it is worth the effort depends on your state's fee schedule and how many dual-eligible patients you see.
What to do this week
- Pull every Medicare remit from the last 90 days and search for remark codes N781, N782 and N783; list the accounts.
- Check each listed account for patient payments or statements and stop any statement, collections or payment plan activity on them.
- Refund any amounts collected, document each refund, and recall any accounts placed with a collections agency.
- Add a "Medicare QMB" patient class or flag in the practice management system with a zero-copay rule and a statement hold.
- Confirm your eligibility tool displays QMB status in the Medicare response and train the front desk to record it at every visit.
- Create a QMB cost-sharing adjustment code so write-offs are reportable and separate from contractual adjustments and bad debt.
