Medicaid can open a coverage window that ended three months ago, and it can close one that was open when the claim went out. Both events change who owes you money. The first is a claim you still get to file. The second is a refund demand that usually arrives as an offset on a remittance you were counting on.
What this covers
- A new applicant can still be covered for up to three months before the month of application, and that window narrows to one or two months for applications filed on or after January 1, 2027.
- The claim clock for a retroactive period usually starts at the eligibility determination date, not the date of service.
- Retroactive months are paid by fee-for-service Medicaid in most states, so a claim sent to the patient’s managed care plan rejects even when the patient is enrolled.
- When coverage is removed for a past period, the payer recoups with claim adjustment reason code 27 or 200 and often takes the money from a future remittance.
- The appeal window on a recoupment is short and set by the payer, and a missed window ends the argument regardless of merit.
The retroactive period is a claim you were allowed to file late, and the deadline sits on a notice the patient may not think to send you.State provider manuals tie the filing clock to the eligibility determination date, not to the date of service.
Most practices treat eligibility as a fact that is checked once and filed away. Medicaid does not work that way. The state can decide in November that a patient was covered in August, and it can decide in November that a patient was not covered in August after all. The first decision pays claims that already denied. The second turns paid claims into overpayments, and the payer collects by withholding money from a batch you have already earned.
What retroactive eligibility is, and what changes in January
Section 1902(a)(34) of the Social Security Act and 42 CFR 435.915 require the state to make eligibility effective no later than the third month before the month of application when two conditions hold: the person received covered services in that period, and the person would have been eligible at the time if an application had been filed then. The applicant has to claim it, and the application has to list the medical bills.
| Group | Applications through 2026 | Applications from January 1, 2027 |
|---|---|---|
| Adult expansion group, ages 19 to 64 | 3 months | 1 month |
| All other federally funded groups | 3 months | 2 months |
| State funded coverage, such as Pennsylvania General Assistance | 3 months | 3 months, a state option |
| CHIP | Optional, up to 3 months | Optional, no earlier than 2 months |
Section 71112 of P.L. 119-21, the Working Families Tax Cut legislation, made that change by amending sections 1902(a)(34) and 1905(a) of the Act. It applies to applications filed on or after January 1, 2027. Pennsylvania put the rule into provider language in Medical Assistance Bulletin 99-26-08 on October 1, 2026, and other states are issuing the same bulletins now.
The new limits attach to the date of the application, not the date of the service. A family that applies on December 30, 2026 keeps the three month window for services back to September. The same family applying on January 5, 2027 gets two months, or one if the adult qualifies through the expansion group. Nothing about the care changes, only the filing date of the application, which makes a pending application worth a phone call in December.
The state also has to find that the person would have been eligible then, applying the application’s income and household information backwards. That is the part which later reverses.
Two directions on the same ledger
The remittance advice tells you which direction you are in. When coverage is added for a past period, a claim that denied for no eligibility can be resubmitted and paid. When coverage is removed for a past period, a paid claim becomes an overpayment and the payer wants it back. Both use the same family of adjustment codes.
| Code | X12 wording | What it means in this work |
|---|---|---|
| 26 | Expenses incurred prior to coverage | Coverage exists now but the state has not extended it back to this date. Resubmit once the period is granted. |
| 177 | Patient has not met the required eligibility requirements | Same denial family. The fix is proof of coverage for the date, not a corrected procedure code. |
| 27 | Expenses incurred after coverage terminated | Coverage ended before the date of service. With a retroactive termination, this is a takeback. |
| 200 | Expenses incurred during lapse in coverage | The state shows a gap. Ask which months it closed and why. |
| 109 | Claim/service not covered by this payer/contractor | Wrong payer for the date. Common when retroactive months are fee-for-service and the claim went to a plan. |
All five codes are current in the X12 adjustment reason list. Two of them describe the same claim at different moments. A claim denied with 26 in March can be paid after a June determination, and a claim paid in March can be reversed in June with 27. One worklist per patient, keyed on the date of service and the eligibility span, shows both events in the same place.
Volume is not evenly spread. One eligibility change on an inpatient stay moves more money than a hundred office visits, so the denial management file should carry the eligibility span next to the claim status.
Working the grant side: the clock starts at the determination
The federal floor lets a state require claims within 12 months of the date of service (42 CFR 447.45(d)(1)), and most states shorten it. Applied literally to a retroactive period, that rule would make part of the period unbillable on the day it is granted, so states write an exception. The exception is where practices win or lose the money.
| State | Rule for a retroactive period |
|---|---|
| Texas | The 95 day filing deadline does not begin until the eligibility notice is received and the client is added to the state eligibility file. |
| Virginia | A retrospective service authorization must be requested within 90 calendar days of the eligibility determination date, and a late request is denied for timeliness. |
| Montana | 12 months from the latest of the date of service or the date retroactive eligibility is determined. |
| Iowa | Retroactive eligibility claims must reach the state within 365 days of the notice date, filed on paper with the notice attached. |
Read your own state manual before borrowing those numbers. The pattern matters: the clock starts at the determination, and the authorization clock can be shorter than the claim clock. In Virginia the authorization has to be in hand inside 90 days, so the practice cannot wait for the claim to reject.
The payer for those months is usually fee-for-service Medicaid. Texas states it plainly in its provider manual: managed care enrollment is generally not retroactive, and a client is enrolled in fee-for-service first, with the health plan carrying a separate eligibility date. A claim for a retroactive month sent to the plan the patient joined this week rejects with 109. Send it to the state processor with the eligibility span on the claim, even when the current card carries a plan name.
If the patient paid anything toward a service inside the retroactive period, the practice refunds it before billing Medicaid. Texas makes the refund a condition of billing the period, and 42 CFR 447.15 requires a Medicaid provider to accept the state payment as payment in full for a covered service. A practice that keeps a card payment and then bills Medicaid has created a beneficiary overpayment.
A practice can decline to accept Medicaid for a retroactive period, and in Texas that choice has to be a written policy applied to every patient and disclosed before the service. Without that policy in place, the period is a covered service and the balance is not the patient’s to pay. The rendering provider also has to be enrolled with the state for those dates, so the credentialing record and the eligibility record have to agree before the claim is worth building.
Save the screen with the date and time of the check and its reference number.
Fee-for-service or managed care, and which plan ID applies to the dates. The current card answers a different question.
Find the state’s retrospective authorization window and file inside it, before the claim.
Post the refund, keep the receipt, then submit the claim and log the determination date.
Why money leaves months later
A retroactive termination is a decision that coverage did not exist for a period the state had already paid. It reaches a practice in three forms: a re-adjudicated claim on a remittance, an offset against a future batch, or a demand letter with a deadline. The first two do not look like a denial, and the third goes to a mailing address nobody reads.
- A renewal finds income or household composition that does not support the months already paid.
- Another payer is found for the period, and the claim moves to coordination of benefits (22).
- The enrollment record carried a wrong member ID or plan, and the correction moves the effective date.
- Medicare or another coverage is granted retroactively, which changes the primary payer for those months.
The last one catches dually eligible patients and anyone whose disability application was approved late. Medicaid is the payer of last resort, so a retroactive Medicare entitlement can pull months of claims back from Medicaid, and Medicaid recovers what it paid. The practice does not choose which payer reviews the claim. It does control whether the file supports the dates the new payer applies.
Federal rules require the state to send notice at least 10 days before the date of a termination or reduction (42 CFR 431.211), and the notice carries the effective date, the reason and the hearing rights. When a patient mentions a letter about coverage, ask for a copy. That notice is usually the only document that establishes the dates the payer is using.
The appeal window is short and it is not the same everywhere
A recoupment is an initial determination, and it starts an appeal clock. The clock comes from the payer, and the payer’s own letter states it.
| Payer | Deadline to dispute | What happens to the offset |
|---|---|---|
| Medicare, original Part A and B | 120 calendar days from receipt of the initial determination, presumed 5 days after the notice date (42 CFR 405.942) | Recoupment cannot start before 41 days, and must stop on a timely redetermination request (42 CFR 405.379) |
| Medicaid fee-for-service, Texas example | 120 days from the disposition date on the remittance that carries the claim | Set by state rule. The state reviews appeals filed within 18 months of the date of service. |
| Medicaid, other states | Set in the provider manual or administrative code, and windows of 30 days appear | Varies. Some states pause recovery on a timely appeal and others do not. |
| Group health plan under ERISA | At least 180 days from the adverse benefit determination (29 CFR 2560.503-1(h)(3)(i)) | Plan and contract terms control, including any right to offset |
The date on the demand letter starts the clock, not the date the money left the account. A practice that finds a takeback during a bank reconciliation has usually spent a month of a 120 day window. One rule prevents that: read every remittance for adjustment codes in the 20s and 100s before posting, and send anything with 27 or 200 to a person the same day.
Pull the demand letter and the remittance that carried the recovery.
Eligibility history for the disputed dates from the state portal, not from the payer’s summary.
Date of service, authorization, eligibility span, payer of record, and the rendering provider’s enrollment status on that date.
Submit the dispute, ask in writing whether the request stops the offset, and escalate to provider relations or the state appeal unit if collection continues.
Re-verify the visits where the money is
Eligibility verification is cheap per transaction and close to worthless when it happens once a year. The encounters that deserve a second check carry five figure exposure: inpatient admissions, surgical cases, infusion and oncology, advanced imaging, equipment, and a month of applied behavior analysis hours.
- The eligibility span, not a yes or no answer.
- The plan name and the health plan name, because they differ for a retroactive month.
- The date and time of the check, plus the reference number the portal returns.
- The coordination of benefits answer, so a second payer is known before the claim is built.
For behavioral health the exposure concentrates fast. A child diagnosed in September often applies for Medicaid in October, and the retroactive period can cover a month of technician hours delivered under a commercial authorization. The Medicaid plan will not honor the commercial authorization, the retroactive months are usually fee-for-service, and a retrospective authorization request can close before the claim window does. An agency that waits for the claim to reject has lost both clocks.
That supports one operational rule: verify at the point of service, re-verify before any scheduled high dollar encounter, and run a look back on every patient whose coverage changed in the last 90 days. The related work on medical billing services treats eligibility as part of the same file as coding and payment posting, because a claim that dies on dates cannot be rescued by a cleaner code.
Questions about retroactive eligibility and takebacks
Yes, if the service falls inside the retroactive span, and the patient payment comes off first. Refund what the patient paid, keep the record of the refund, then file the claim. A practice that bills Medicaid while holding a patient payment has created a beneficiary overpayment, and 42 CFR 447.15 limits the provider to the state payment for a covered service.
For applications filed through December 31, 2026, up to three months before the month of application, under 42 CFR 435.915. For applications filed on or after January 1, 2027, section 71112 of P.L. 119-21 limits the period to one month for adult expansion enrollees and two months for everyone else. State funded coverage can keep the longer period.
Not for a service Medicaid covered, because the provider accepted the state payment as payment in full. If the termination is wrong, the answer is a dispute with the state, not a new invoice. For commercial coverage, the contract and the plan’s appeal rights decide, and a patient balance is usually the last step rather than the first.
It is state specific, and the demand letter states it. Medicare allows 120 days for a redetermination under 42 CFR 405.942, Texas Medicaid allows 120 days from the remittance disposition date, and ERISA group health plans must allow at least 180 days. Several state Medicaid programs allow 30 days, so diarize from the notice date, not the date the money moved.
Generally no. Managed care enrollment usually starts later than the coverage, so the retroactive months are paid by fee-for-service Medicaid even when the patient is enrolled in a plan now. Texas states this in its provider manual, and most other states apply the same sequence. Confirm the payer for the dates before the claim goes out.
The patient is the fastest source, since the approval notice goes to them, and the state portal is the reliable one. Query the eligibility history for prior dates of service on every patient whose coverage changed, and run a monthly look back on open balances. A report on denied and unbilled claims older than 60 days catches most grants before the window closes.
The bottom line
Retroactive eligibility is a date problem before it is a billing problem. The state decides whether coverage existed, and the payer decides whether it still does. A practice that records the determination date, the payer of record for each span, and the appeal window on every demand keeps both decisions inside its own control.
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Request a free eligibility auditThis article summarizes federal regulations and published state guidance as of October 2026 and is not legal advice; confirm the current rules with your state Medicaid agency and your payer contracts.
