The overpayment demand letter arrived Monday. What should you have decided by Friday?

The letter is titled Notice of Overpayment, or Request for Refund, or something blander that takes a paragraph to get to the point. It lists claims from last year, a dollar total and a date. The billing manager forwards it to the owner, the owner forwards it to the clinical director, and by Wednesday three people have opinions and nobody has a list. A demand letter is not an emergency in the first hour, but it becomes one if the first week is spent reacting instead of sorting. Here is the order that works.

Day one: read the letter for what it actually claims

A demand letter is a structured document even when it does not look like one. Before anyone argues the merits, one person reads it start to finish and puts these facts on a single page:

• Who sent it. The payer itself, a contractor acting for a government program, a Medicaid program integrity unit, or a commercial plan's payment integrity vendor. The sender determines which rules, appeal rights and contract terms apply.
• What kind of review produced it. Claim-by-claim findings, or a sample whose error rate was extrapolated to a larger set of claims. An extrapolated demand is defended differently, because the method is part of the dispute.
• The claims at issue. Dates of service, claim numbers, billed and paid amounts per line, and the rendering provider where listed.
• The stated reason for each finding, in the payer's own words, with any reason codes.
• The amount demanded and how it was calculated, including interest if the letter mentions it.
• Every date in the letter: response, appeal, repayment, and the date the payer says it will begin offsetting the balance against future payments.
• The appeal or dispute rights described, and exactly where a response has to go.

Then write down what the letter does not say. A total with no claim-level detail, a finding with no stated reason, an extrapolated amount with no description of the sample: those are things to request in writing, not things to guess at.

Protect every deadline before anyone argues the merits

The most expensive mistake in the first week is losing an appeal right because the deadline sat in someone's inbox. Deadlines vary by payer, program and contract, so read them from the letter and confirm them against the applicable contract, state rule or regulation. For traditional Medicare, the appeal levels and filing windows are set out in 42 CFR Part 405, Subpart I, and a separate provision at 42 CFR 405.379 limits recoupment while certain appeals are pending. That makes the timing of the first filing a cash question, not just a legal one. Commercial and Medicaid managed care plans set their own terms, and some states regulate how and when plans may recover overpayments.

On day one, do four things:

• Name one owner for the response. Not a department, a person.
• Put each deadline on a shared calendar with reminders well ahead of it.
• Notify your compliance lead and, for any demand of real size or any extrapolated demand, counsel.
• Instruct staff that nothing in the affected charts is edited, completed or reorganized while the response is open.

If a genuine correction is needed, it follows your addendum policy: dated today, signed, with the reason stated, and never backdated. The distinctions matter, and they are covered in late entries, addenda and amendments to signed notes.

Reconcile the payer's list against your own ledger

Before anyone debates medical necessity, check the arithmetic. Payment integrity reviews run on claims data, and claims data carries errors on both sides.

1. Match every claim on the list to your billing system: billed amount, adjudicated amount, paid amount and payment date.
2. Check whether any listed claim was already voided, corrected, refunded or offset. A corrected claim and its original can both end up on a demand.
3. Confirm the patient, date of service, billing entity and rendering provider match what you submitted.
4. Total the paid amounts yourself and compare with the demanded total.
5. Flag any claim you cannot find at all.

Say a hypothetical residential program receives a demand covering 40 bed-days. Reconciliation shows three were refunded months ago when a corrected claim went out, and two were billed under a sister facility's tax ID. Those five come off the list, in writing, before a single chart is pulled. Arithmetic disputes are the cheapest wins available, and they are easy to miss once the conversation turns clinical.

Sort the findings by reason, because each reason has a different defense

Group the remaining claims by the payer's stated reason. Each group points to different evidence and usually a different owner:

• Documentation missing or unsigned. Does a signed note exist for the date, dated before the claim? Owner: clinical records.
• Medical necessity. Does the assessment, treatment plan and progress documentation support the level of care for those dates? Owner: clinical director or utilization review.
• Authorization. Was an authorization in place covering the dates, units and level of care billed? Owner: utilization review.
• Provider eligibility. Was the rendering clinician licensed, enrolled with that payer and supervised as required on the date of service? See proving eligibility on the date of service. Owner: credentialing.
• Coding, units or modifiers. Does the claim match what the documentation describes? Owner: billing and coding.
• Duplicate billing or coverage. Was the service billed twice, or was the patient covered by another plan? Owner: billing.

Sorting this way turns one intimidating letter into five or six smaller questions, each with someone accountable for answering it.

Pull a sample and score it honestly

You do not need to rebuild every chart in week one. Pull a handful of records from each reason group and have them scored by people who were not involved in the original billing, ideally a clinical reviewer and a billing reviewer working together. For each claim the question is narrow: does the record, as it existed on the date of service, support the claim as billed, partially support it, or not support it?

Be harder on your own records than the payer was. A reviewer who wants the appeal to succeed will read a thin note generously, and the payer will not. If the demand is large or extrapolated, consider running this review at counsel's direction so the work is handled appropriately.

The sample result is what drives the decision. If a reason group largely holds up, it is worth appealing. If it largely fails, defending it spends staff time and credibility you will want for the claims you can win.

Appeal, repay or request records: choosing per group

Most demands end up split. Treat the decision as one per reason group, not one for the whole letter.

Appeal

Appeal where the records support the claim as billed and the reconciliation found errors. Appeal claim by claim, cite the specific page that answers the specific finding, and do not pad the response with the whole chart. For an extrapolated demand, both the individual sample claims and the sampling method can be challenged, and the method usually needs someone qualified to examine it. Overturning sample claims can change the extrapolated total, which is why the sample claims deserve the most careful work.

Repay

Repay where the finding is right. Ask the payer what repayment options exist, such as a lump sum, an extended repayment arrangement or offset against future payments, and get the terms in writing. Model the cash impact first: an offset that withholds a month of remittances from your largest payer can hurt more than a planned repayment. A correct finding is also a compliance event, so it should produce a fix to whatever workflow failed, not just a check.

Request records or clarification

Request more information where the letter lacks claim-level detail, a stated reason or a description of the sampling method. Do it in writing and keep proof of what you asked and when. Confirm whether a request pauses any deadline; often it does not, and an appeal right can lapse while you wait for an answer.

Friday: write the decision down

By the end of the week the owner should circulate a one-page decision memo: the reconciled claim list, the reason groups, the sample results, the decision for each group, the deadline and owner for each action, and the expected cash impact of any repayment or offset. That memo is what the owner, compliance lead and counsel sign off on, and it is what you will want in the file if the matter is still open a year from now.

Then ask the question the letter was really asking: which upstream workflow let these claims go out? An authorization nobody watched, a note signed after billing, a clinician billing before enrollment was effective. The repayment closes this letter. The fix is what stops the next one.

If your appeal deadlines currently live in someone's inbox, a denials queue that carries the dollars at risk, the deadline and a named owner on every item keeps them visible. And when the appeal needs the signed records for specific dates of service, audit response packets compile them into one indexed, paginated document.

Frequently asked questions