Timely Filing Limits by Payer: The Year-End A/R Sweep

The Medicare timely filing limit is one calendar year from the date of service, set by 42 CFR 424.44. Medicaid and commercial limits come from state rules and payer contracts, so they differ by payer. A year-end sweep protects that revenue only if it sorts aged claims by filing deadline, not by balance or age.

Every December, some practices write off claims that were perfectly collectible in October. The work wasn’t hard. The claims were just at the bottom of a list sorted the wrong way. This post covers the payer-side deadlines and how to run the sweep. For the patient side, meaning how long a balance can be pursued with the patient, see how long a medical claim can be collected.

Medicare: one calendar year, measured precisely

42 CFR 424.44(a)(1) says a claim for services furnished on or after 1 January 2010 must be filed “no later than the close of the period ending 1 calendar year after the date of service.” The Medicare Claims Processing Manual, Chapter 1, §70, shows how that works in practice:

• The clock starts on the date of service (§70.1). On professional claims with span dates, the line-item “From” date controls. A service on 29 February must be filed by 28 February of the following year.
• The clock stops on receipt by the right contractor (§70.3). A claim sent to the wrong Medicare contractor isn’t a claim until the right one receives it (§70.2.1).
• Returned submissions don’t count. A submission that is incomplete or invalid, such as one with a wrong Medicare beneficiary identifier or an invalid procedure code, is returned and is not considered filed for timely filing purposes (§70.2.3 and §70.2.3.1). The manual contrasts this with rejections, which can be corrected and resubmitted, and denials, which can be appealed (§70.2.3.2).
• An untimely denial is final (§70.4). It isn’t an initial determination, so it can’t be appealed. In general the provider can’t bill the beneficiary for the service either, apart from the deductible and coinsurance that would have applied anyway.
• You can’t add a line after the deadline (§70.5). A missed item or service can’t be added once the original claim’s filing period has passed.

The regulation allows a few exceptions (§424.44(b)), including an error or misrepresentation by CMS or its contractor, retroactive Medicare entitlement, and retroactive Medicare Advantage disenrollment where the plan recovers its payment six months or more after the service. Each extends the deadline through the last day of the sixth calendar month after the triggering notice or recovery. If the deadline falls on a weekend or federal holiday, it moves to the next workday (§424.44(c)). Treat that as a safety margin, not a plan.

What that means this quarter: Medicare services from October, November and December 2025 reach their one-year limit in October, November and December 2026. An 18 November 2025 visit has to be received by 18 November 2026.

Medicaid and commercial: read the contract, not a chart

For Medicaid, the federal rule at 42 CFR 447.45(d)(1) requires the state agency to have providers submit all claims no later than 12 months from the date of service. A related provision, §447.45(d)(4)(ii), lets the agency pay a Medicaid claim within 6 months after notice of the Medicare decision when the Medicare claim was filed on time. That matters for dual-eligible crossovers. States and Medicaid managed care plans publish their own deadlines in provider manuals and contracts.

Commercial deadlines are contract terms. They vary by payer, by product and sometimes by state law. We’re not going to print a chart of “typical” commercial limits. A number from someone else’s chart is exactly how practices miss the one in their own contract. Build your own table from your contracts, with four columns per payer:

1. Initial claim filing limit, and whether it runs from the date of service or the discharge date.
2. Corrected (replacement) claim limit.
3. Appeal or reconsideration limit, and what starts that clock.
4. Secondary-claim limit after the primary payer’s remittance.

Corrected claim, reopening or appeal?

Choosing the wrong path wastes time you may not have.

• Returned claim: it was never a claim, so fix it and file it inside the original filing limit.
• Rejected claim: correct it and resubmit, and don’t assume the rejection paused the filing clock.
• Medicare clerical error on a processed claim: a party can ask the contractor to reopen an initial determination within 1 year for any reason, within 4 years for good cause, or at any time to correct a clerical error in an unfavorable determination (42 CFR 405.980(c)).
• Medicare denial you dispute: request a redetermination within 120 days of receiving the initial determination, which is presumed to be 5 days after the notice date (42 CFR 405.942).
• Commercial denial: a corrected claim or an appeal, depending on the contract. Each has its own clock, per column 2 or 3 of your table.

CARC 29 and proof of timely filing

When a payer decides you missed the window, the remittance carries CARC 29: “The time limit for filing has expired” (X12 code list). For Medicare, check whether a §424.44(b) exception applies. If none does, the §70.4 rule applies: no appeal and no patient bill.

For commercial payers, how a CARC 29 is disputed depends on the contract’s appeal terms, and the case rests on proof that the claim arrived on time. Keep, for every claim:

• The payer’s acknowledgment of receipt, not only the clearinghouse’s acceptance report.
• The original submission date and the claim number of any earlier version.
• Correspondence showing the payer asked for information or had the claim in process.

Our guide to CARC and RARC codes covers reading the rest of the remittance.

Running the year-end sweep

1. Pull all open insurance A/R with payer, date of service, first-submission date, last action and last remit code.
2. Bucket by age in your usual 30-day aging buckets for reporting, but don’t work from the buckets.
3. Add a “deadline” column: date of service plus that payer’s limit from your table. Add “days remaining.”
4. Sort by days remaining, ascending. Anything under 45 days goes to the top, regardless of balance.
5. Split by status: never billed or returned (file now); rejected (correct and file); denied and fixable (corrected claim or reopening); denied and disputed (appeal, with its own deadline); CARC 29 received (exception or proof).
6. Work Medicare Q4 2025 dates of service first. Their one-year clock is closing now, and a missed Medicare deadline can’t be appealed.
7. Document every touch so the next person can see what was sent and when.

For benchmarks to measure the result, see days in A/R: how to calculate it. Denial and A/R worksheets are in our resources library.

If your aged A/R is bigger than your team can sweep before year-end, A/R follow-up is part of the medical billing services AMS has provided since 1992.