Guide

Timely filing: the clocks, the proofs, the exceptions

Summary

Medicare sets one federal timely-filing deadline — 12 months from the date of service — published in its own claims-processing manual. Every other payer's deadline is a term of that specific participation contract, not a universal number, so the reliable check is always that payer's current published policy rather than a remembered figure. Self-funded ERISA plans layer their own claims-and-appeals framework on top of whichever deadline the plan document sets.

By Gale Editorial · Updated 2026-07-26. Every figure cited to a dated source. How we write.

The one federal anchor: Medicare's 12 months

Medicare's timely-filing deadline is set out in the Medicare Claims Processing Manual, one of CMS's public Internet-Only Manuals, and it runs 12 months from the date of service for the large majority of claims 1Ref 1Centers for Medicare & Medicaid Services (2026).Internet-Only Manuals (IOMs).That CMS program instructions live in the public Internet-Only Manuals, including the Medicare Claims Processing Manual's 12-month timely-filing rule and its defined exceptions.. That manual also defines a short, specific list of exceptions to the general rule.

Those exceptions are worth looking up directly in the manual itself rather than assuming one applies, since a claimed exception that doesn't actually fit the defined criteria doesn't extend the deadline it was meant to cover — it just delays the moment the claim gets denied for filing late.

This is the one number in timely filing that's genuinely universal across the program rather than payer-specific, which is exactly why it's worth distinguishing clearly from everything that follows. Treating it as the template for every other payer's deadline is the single most common mistake in this entire area of billing.

Why timely filing lives in the contract for everyone else

Outside Medicare, there is no single federal timely-filing number — the deadline for a commercial payer is a term of the specific participation agreement a practice signed, which is why two practices billing the same insurer in the same state can be working against genuinely different clocks if they signed at different times or under different network products.

That's also why a timely-filing number learned from a peer, a prior job, or a training years ago should never be trusted for a current contract without checking: the number isn't wrong because it was misremembered, it's wrong because it was never universal to begin with, and the only version that controls is the one written into the agreement currently in effect.

A practice with contracts across several payers is really tracking several independent deadlines at once, not one deadline with a few payer-specific exceptions, and it's worth organizing the practice's own records around that reality rather than around a single assumed number. The short version worth remembering is that timely filing lives in the contract, not in a rule you can look up once and apply everywhere.

What 'payer-specific' actually looks like in practice

Cigna, Anthem, Aetna, and UnitedHealthcare each publish their own coverage and reimbursement policies, including timely-filing terms, on their own provider portals 2Ref 2Cigna (2026).Cigna Coverage and Claims Policies.Cited as a named example of a payer publishing its own timely-filing and reimbursement policy on its own portal, used only to illustrate where the real answer for a specific contract lives, not as a claim about what all payers require.3Ref 3Anthem (2026).Anthem Provider Policies.Cited as a named example of a payer publishing its own timely-filing and reimbursement policy on its own portal, used only to illustrate where the real answer for a specific contract lives, not as a claim about what all payers require.4Ref 4Aetna (2026).Aetna Clinical Policy Bulletins.Cited as a named example of a payer publishing its own timely-filing and reimbursement policy on its own portal, used only to illustrate where the real answer for a specific contract lives, not as a claim about what all payers require.5Ref 5UnitedHealthcare (2026).UnitedHealthcare Policies and Protocols.Cited as a named example of a payer publishing its own timely-filing and reimbursement policy on its own portal, used only to illustrate where the real answer for a specific contract lives, not as a claim about what all payers require. — not because these four necessarily use identical windows, but because each is a concrete example of where the real answer for a specific contract actually lives.

That real answer lives in that payer's own current published policy, not in a table copied from memory or passed along secondhand. A number that was accurate for a contract signed two renewal cycles ago is not a safe substitute for checking the current policy on file today.

The habit worth building is pulling the current policy directly whenever a new payer relationship starts, and re-checking it after any contract renewal, rather than assuming a deadline confirmed once stays accurate indefinitely. A short note in the payer's own file, dated when it was last confirmed, makes this a five-minute task instead of a fresh search each time.

ERISA self-funded plans run their own clock

A self-funded employer health plan is governed by ERISA rather than by state insurance law, and ERISA sets its own claims-and-appeals framework instead of adopting a state's prompt-pay or filing-deadline statute 6Ref 6U.S. Department of Labor (2026).ERISA.That self-funded employer plans are governed by ERISA rather than state insurance law, which is why the plan document rather than the insurer's standard published policy sets the timely-filing deadline for those plans.. That matters here because a plan administered by a familiar-looking commercial insurer can still be self-funded underneath.

In that case, the plan runs on the terms of that specific plan document rather than the insurer's standard published policy for its fully-insured products — the deadline that applies to one patient covered by a given insurer's fully-insured plan may not be the deadline that applies to another patient covered by that same insurer's self-funded employer plan.

There's often no easy way to tell from the insurance card alone whether a given employer plan is self-funded, which is one more reason the safest habit is confirming the specific deadline in writing for a new employer-group patient rather than assuming it matches the insurer's general policy.

Proving you filed on time when a payer says you didn't

A timely-filing denial is disputed with proof of the original submission date — a clearinghouse acceptance report, a certified-mail receipt for a paper claim, or an EDI acknowledgment timestamped before the deadline — filed as an appeal with that proof attached, not as a corrected claim, since nothing about the clinical content or the coding is in question.

Building that specific appeal is worth treating as its own routine within a practice's broader approach to denials-appeals, rather than a scramble assembled fresh every time one arrives. Having the proof format ready in advance turns a stressful dispute into a five-minute submission.

Keeping submission confirmations filed by date, rather than trusting they can always be pulled from the clearinghouse's own archive on demand, is what makes that proof available quickly when a denial actually shows up. A clearinghouse's own retention window for old confirmations is not guaranteed to match how far back a payer might look.

Why resubmitting isn't the same as tracking the deadline

Refiling a claim that already reached the payer once, just as a precaution, isn't a substitute for tracking the actual filing deadline, and it carries a real risk of its own: a payer's system may flag the resubmission against its own duplicate edits rather than treat it as a fresh, timely attempt.

That flag adds a second problem on top of whatever caused the original submission to look late in the first place, and untangling a duplicate-edit flag from an actual filing-deadline question takes longer than either issue would have taken on its own.

The more reliable habit is tracking the actual deadline for each active payer relationship directly — on a calendar or in the practice-management system — rather than relying on resubmission as insurance against a deadline nobody is actually watching. A tracked deadline gets a proactive submission; an untracked one gets a defensive resubmission after the fact, and only one of those is actually reliable.

Common questions

12 months from the date of service for the large majority of claims, set out in the Medicare Claims Processing Manual. That manual also defines a short list of specific exceptions to the general rule, and they're worth checking directly in the manual itself rather than assuming one applies to a particular claim.

No. Each payer's deadline is a term of the specific participation agreement a practice signed, so two practices billing the same insurer can face different deadlines depending on when and under which contract they signed. The only reliable source is that payer's current published policy.

Not necessarily. A self-funded employer plan is governed by ERISA, which sets its own claims-and-appeals framework, and the actual filing deadline is whatever that specific plan document specifies — not necessarily the same insurer's standard published policy for its fully-insured products.

File an appeal with proof of the original submission date attached — a clearinghouse acceptance report, a certified-mail receipt, or a timestamped EDI acknowledgment. This is an appeal, not a corrected claim, because nothing about the coding or clinical content is in dispute.

Resubmitting isn't a safe substitute for tracking the actual deadline — a payer's system may flag the resubmission as a duplicate rather than a timely fresh attempt, adding a second problem. Tracking each payer's real deadline directly is more reliable than resubmitting as a precaution.

Run your practice on Gale

The software is free. Gale earns one flat 3.5% all-in per paid transaction — only on transactions that actually pay. No subscription, no setup fee, no network cut.

Start or manage a practice →

References

1.Centers for Medicare & Medicaid Services (2026). Internet-Only Manuals (IOMs). Centers for Medicare & Medicaid Services (CMS). link ✓That CMS program instructions live in the public Internet-Only Manuals, including the Medicare Claims Processing Manual's 12-month timely-filing rule and its defined exceptions.
2.Cigna (2026). Cigna Coverage and Claims Policies. Cigna provider portal. link ✓Cited as a named example of a payer publishing its own timely-filing and reimbursement policy on its own portal, used only to illustrate where the real answer for a specific contract lives, not as a claim about what all payers require.
3.Anthem (2026). Anthem Provider Policies. Anthem provider portal. link ✓Cited as a named example of a payer publishing its own timely-filing and reimbursement policy on its own portal, used only to illustrate where the real answer for a specific contract lives, not as a claim about what all payers require.
4.Aetna (2026). Aetna Clinical Policy Bulletins. Aetna provider portal. link ✓Cited as a named example of a payer publishing its own timely-filing and reimbursement policy on its own portal, used only to illustrate where the real answer for a specific contract lives, not as a claim about what all payers require.
5.UnitedHealthcare (2026). UnitedHealthcare Policies and Protocols. UnitedHealthcare provider portal. link ✓Cited as a named example of a payer publishing its own timely-filing and reimbursement policy on its own portal, used only to illustrate where the real answer for a specific contract lives, not as a claim about what all payers require.
6.U.S. Department of Labor (2026). ERISA. U.S. Department of Labor. linkThat self-funded employer plans are governed by ERISA rather than state insurance law, which is why the plan document rather than the insurer's standard published policy sets the timely-filing deadline for those plans.

https://www.gale.care/for-providers/cm-timely-filing-limits · 6 sources. Competitor details are cited to dated public sources and maintained as they change; figures are estimates, not commitments. Synthetic demonstration.

← Back to for providers