Overpayment Demand Letter: A Behavioral Health Response
Answer an overpayment demand before offset starts: Medicare day counts, extrapolation questions, state recoupment limits, appeals, and a dispute letter.
On this page: Direct answer
Direct answer
Overpayment demand letter response: what operators need to know
Answer an overpayment demand before offset starts: Medicare day counts, extrapolation questions, state recoupment limits, appeals, and a dispute letter. Calendar the demand the day it arrives; the dispute deadline, the offset date, and the appeal deadline are different dates.
An overpayment demand says a payer has concluded it paid you too much and wants the money back, by refund, by offset against claims you are still submitting, or both. When the demand follows a records request or a prepayment round, a set of claims has been reviewed, errors have been found, and sometimes the error rate has been projected across claims no one reviewed.
The first weeks after the letter decide how much leverage you keep. Medicare begins standard recoupment on day 41 unless a qualifying appeal arrives first, and CMS's own fact sheet tells providers to file a redetermination by day 30 to prevent it. Commercial plans follow contracts and state law; UnitedHealthcare's 2026 guide, for example, offsets audit findings after 45 days unless you have paid or sent written disagreement.
This guide is operational, not legal advice. Bring in counsel for extrapolated demands, large dollar amounts, or any demand that comes from a special investigations unit or program-integrity contractor.
Key takeaways
The short version
- Calendar the demand the day it arrives; the dispute deadline, the offset date, and the appeal deadline are different dates.
- In Medicare, a timely redetermination request stops recoupment on qualifying overpayments; a rebuttal does not.
- An extrapolated demand is only as good as its sample; request the universe, sampling frame, and claim-level worksheet.
- State recoupment limits vary widely and protect state-regulated insured plans; self-funded employer plans may fall outside them.
- Contest claim by claim with page citations, and repay what the record does not support.
Take the template with you
Free to copy · no email required
A notice of disagreement that disputes claim by claim, concedes what the record does not support, requests the sampling materials behind any extrapolation, and asks the payer to hold offset. Confirm the track and deadline in the demand before sending.
One row per demanded claim: position (agree, dispute, recode), supporting page, offset taken, appeal level, and deadline. Use claim references, not patient identifiers.
claim_ref,date_of_service,code_billed,paid_amount,amount_demanded,payer_reason,sampled_or_projected,our_position,supporting_page,recode_to,amount_if_recoded,offset_taken,offset_remit_ref,appeal_level,appeal_deadline,filed_date,outcome,notes ,,,,,,,,,,,,,,,,,
1. Read the demand before you argue it
Check the notice against the rules for that payer before arguing the merits. A Medicare demand letter explains how the overpayment was calculated, lists the services involved, and describes interest, repayment options, recoupment, rebuttal, and appeal rights. New York requires health plans to give 30 days' written notice with the patient name, service date, payment amount, proposed adjustment, and a reasonably specific explanation. Texas requires the basis and specific reasons for the recovery. Then confirm each element below.
| Element | What to confirm | Why it matters |
|---|---|---|
| Issuer and program | Plan, product, contractor, and whether the plan is insured or self-funded | Selects the appeal track and whether state law applies |
| Claim list | Each claim, date of service, amount paid, and amount demanded | You cannot dispute a total, only claims |
| Basis | A specific reason for each claim | Vague reasons are the first thing to challenge |
| Calculation | Actual claim-level amounts or a projection from a sample | Extrapolated demands need a different response |
| Deadlines | Refund date, dispute or rebuttal window, appeal deadline | Each carries a different consequence |
| Offset terms | When and how the payer will withhold from current payments | Offsets hit claims unrelated to the review |
2. Work the clock first
Medicare publishes its schedule, and the appeal rules drive it. A timely and valid redetermination request makes the contractor stop recoupment of that overpayment, and a timely reconsideration request does the same at the next level. After an unfavorable redetermination, recoupment can resume on the 60th day unless a reconsideration request arrives, so file within 60 days to keep it paused even though the regulation allows 180 days to file. Once the reconsideration is decided, recoupment continues through later appeal levels; interest accrues throughout and is adjusted if you win.
The table below follows CMS's overpayment fact sheet for overpayments subject to the recoupment limitation, counted from the date of the demand letter.
| Day | What happens |
|---|---|
| Day 15 | Last day to submit a rebuttal, which does not stop recoupment |
| Day 16 | Immediate recoupment begins if you requested it |
| Day 30 | File a redetermination by this day to prevent recoupment from starting on day 41; pay in full by now to avoid interest |
| Day 31 | Interest accrues on unpaid balances, even if you have appealed |
| Day 41 | Standard recoupment begins unless the overpayment is in an excluded status, such as a pending redetermination |
| Days 61-90 | Intent-to-refer letter for eligible delinquent debt |
| Day 120 | Last day to file a redetermination |
| Days 126-150 | Referral of delinquent debt to the Treasury |
3. Test an extrapolated demand
Before Medicare can extrapolate, there must be a determination of a sustained or high level of payment error, or documentation that educational intervention failed. By law that determination is not subject to administrative or judicial review, so the dispute is over execution: the universe, the sample, and the claim-level findings.
Medicare's manual requires the demand or final results to explain the sampling methodology: a description of the universe, sampling frame, and method; the sampling unit; the selection procedure and any strata; the review period; the estimation method and sampling error; and the actual overpayment or underpayment on each sampled claim. The contractor must keep enough documentation for the sample to be replicated. In most cases the amount demanded is the lower limit of a one-sided 90 percent confidence interval, capped at the total paid in the sampling frame.
Claim-level wins move the total. If an appeal reverses sampled claims, the estimate is recomputed. If the methodology is found invalid, the contractor may correct it, recover only the actual overpayments on sampled claims and start a new review, or redo the review with a valid method.
Commercial plans extrapolate too. UnitedHealthcare's guide describes projecting an error rate from a statistically valid random sample and warns that failing to supply all requested records may fail the entire sample. Its Oxford section reserves extrapolation for suspected fraud or a sustained or high level of billing errors, such as systemic upcoding.
4. Check state recoupment limits, and whether they apply
Several states regulate how insured health plans recover overpayments: the notice they must give, how long they have, and whether they can recover while you dispute. The examples below show how much the rules differ. Check the statute for your state and the plan type before relying on it.
| Rule | What it says | Applies to |
|---|---|---|
| California Health and Safety Code 1371.1 | After written notice identifying the overpayment and amount, the provider repays within 30 working days or contests in writing within 30 working days, naming the contested portion and specific reasons; uncontested amounts then accrue 10 percent annual interest | Health care service plans under chapter 2.2 of the Health and Safety Code |
| New York Insurance Law 3224-b | 30 days' written notice before recovery, with patient, service date, payment, proposed adjustment, and a reasonably specific explanation; no recovery initiated more than 24 months after payment, with exceptions | Health plans; the 24-month limit does not apply to recovery a self-insured plan requires or requests |
| Texas Insurance Code 1301.132 | Notice within 180 days after payment, with the basis and specific reasons; if the provider disagrees, the insurer must offer an appeal and may not recover until appeal rights are exhausted | Preferred provider benefit plans under chapter 1301 |
| Payer addenda (example) | Evernorth's Alabama addendum limits retroactive recoupment to 12 months after payment or the claim-filing period, whichever ends first; its Florida addendum uses 12 months for physicians and certain other licensees and 30 months for other providers, with fraud exceptions | Evernorth's insured business; its addenda state they do not apply to self-funded plans |
5. Build the dispute claim by claim
- 01
Load the claim list into a worksheet
One row per claim: reference, date of service, code, paid amount, amount demanded, stated reason, and whether the claim was sampled or projected.
- 02
Classify every claim
Agree; dispute because the record supports the service as billed; dispute because the reviewer missed enclosed pages; or partial, where the record supports a lower code. Novitas's psychotherapy reviews recode to the level the documented time supports, so ask for recoding rather than full denial where that is what the record shows.
- 03
Cite pages, not arguments
Point each disputed claim to the page in your original submission that answers the stated reason. Add a short clinical explanation only where the reason is medical necessity.
- 04
Repay what the record does not support
Paying agreed amounts promptly limits interest. In Medicare you can request immediate recoupment or, if you cannot pay within the required time, an extended repayment schedule.
- 05
File on the right track
Medicare: redetermination within 120 days (by day 30 to prevent recoupment), then reconsideration within 180 days. Medicaid: the state or managed care plan process. Commercial: the notice-of-disagreement, reconsideration, and appeal steps in the demand and your agreement, then any arbitration the contract provides.
- 06
Approve and send
A named person reviews the worksheet, the letter, and the enclosures before anything goes to the payer. Keep proof of delivery.
6. Manage offset and the exposure behind the demand
- Reconcile every remittance against the demand so finance knows exactly what has been withheld and from which payments
- Ask the payer in writing to hold offset on disputed amounts while the dispute is pending, citing the contract term or statute that supports it
- If a finding reveals a pattern, consider your own obligations: in Medicare, an overpayment you identify must be reported and returned within 60 days, suspended for up to 180 days while you complete a timely, good-faith investigation of related overpayments, with a six-year look-back
- Check whether the same documentation pattern exists in claims to other payers before they find it
- Escalate to counsel for extrapolated demands, large amounts, or any sign of a fraud referral
Common questions
Answers before you build.
Does appealing stop a Medicare recoupment?+
For overpayments subject to the recoupment limitation, yes: a timely and valid redetermination request stops recoupment until the decision, and CMS tells providers to file by day 30 to keep recoupment from starting on day 41. A rebuttal does not stop recoupment, and interest still accrues.
Can a commercial insurer take money from payments on other patients' claims?+
Often, if the contract and state law allow it. UnitedHealthcare, Optum, and Evernorth manuals all describe offsetting overpayments against future payments, subject to the agreement and applicable law. Some contracts pause offset when you disagree in writing on time, such as UnitedHealthcare's 45-day rule for audit findings.
How far back can an insurer recover an overpayment?+
It depends on the program, state, and contract. Medicare contractors can reopen within 1 year for any reason, 4 years for good cause, and at any time for fraud; New York health plans generally cannot initiate recovery more than 24 months after payment; Texas preferred provider plans must give notice within 180 days. Self-funded plans may not be bound by state limits.
Can an extrapolated overpayment be challenged?+
Yes, on execution. In Medicare, the determination that a sustained or high error rate exists cannot be appealed, but the sampling methodology and each sampled claim can be, and reversals on sampled claims reduce the projected amount.
Should we just pay to make it go away?+
Pay what the record does not support and dispute what it does. Paying in full can concede findings you could have reversed, and it does not end your obligations if the review revealed a broader pattern.
Practical closeout
Use this operator checklist.
- Calendar the demand the day it arrives; the dispute deadline, the offset date, and the appeal deadline are different dates.
- In Medicare, a timely redetermination request stops recoupment on qualifying overpayments; a rebuttal does not.
- An extrapolated demand is only as good as its sample; request the universe, sampling frame, and claim-level worksheet.
- State recoupment limits vary widely and protect state-regulated insured plans; self-funded employer plans may fall outside them.
- Contest claim by claim with page citations, and repay what the record does not support.
Continue through the cluster
Verified customer case studies are added only with customer permission and supporting evidence; none is implied by these operational examples.
Sources & methodology
Trace the operational claims.
Marsa Health Editorial reviewed the primary and research sources below on September 21, 2026. We translate them into workflow controls, distinguish proposals from final rules, and flag where plan, program, state, contract, or clinical requirements vary.
- 01Medicare Overpayments (MLN006379) Centers for Medicare & Medicaid ServicesJuly 2025 fact sheet: demand-letter contents, repayment options, rebuttal, recoupment limitation, interest, and the day-by-day debt collection timeline.Accessed or rechecked September 21, 2026
- 0242 CFR 405.379: Limitation on recoupment of provider and supplier overpayments Electronic Code of Federal RegulationsRecoupment may begin no earlier than 41 days after the demand and stops on a timely and valid redetermination or reconsideration request; interest continues to accrue.Accessed or rechecked September 21, 2026
- 0342 CFR 405.942: Time frame for filing a request for a redetermination Electronic Code of Federal RegulationsMedicare redetermination requests are due within 120 days of receiving the initial determination.Accessed or rechecked September 21, 2026
- 0442 CFR 405.962: Timeframe for filing a request for a reconsideration Electronic Code of Federal RegulationsMedicare reconsideration requests are due within 180 days of receiving the redetermination notice.Accessed or rechecked September 21, 2026
- 05Medicare Program Integrity Manual, Chapter 8: Administrative Actions and Sanctions and Statistical Sampling for Overpayment Estimation Centers for Medicare & Medicaid ServicesRev. 13762 (May 2026): conditions for extrapolation, sampling documentation, the one-sided 90 percent lower limit, required methodology disclosures, payment suspension, and the effect of appeals on estimates.Accessed or rechecked September 21, 2026
- 0642 CFR 405.980: Reopening of initial determinations, redeterminations, reconsiderations, hearings, and reviews Electronic Code of Federal RegulationsMedicare contractors may reopen within 1 year for any reason, within 4 years for good cause, and at any time for fraud or similar fault.Accessed or rechecked September 21, 2026
- 0742 CFR 401.305: Requirements for reporting and returning of overpayments Electronic Code of Federal RegulationsIdentified Medicare overpayments must be reported and returned within 60 days, suspended up to 180 days for a timely good-faith investigation, with a six-year look-back.Accessed or rechecked September 21, 2026
- 08California Health and Safety Code Section 1371.1 California Legislative InformationHealth care service plan overpayment notices: 30 working days to repay or contest in writing with specific reasons, and interest on uncontested amounts.Accessed or rechecked September 21, 2026
Organizational author. Editorial review covers source accuracy, search intent, workflow boundaries, and human-oversight requirements. This material is educational and does not provide clinical, legal, coding, or coverage advice.
No named clinical or legal expert reviewer is attributed to this version. Marsa Health does not invent reviewer credentials.
Read our editorial methodRevision history
What changed and when
September 21, 2026
Initial publication, source review, and operational editing.