Guide · Billing
Timely Filing Limits For Behavioral Health Claims
Medicare Part B gives you 12 months from the date of service to file a clean claim. Commercial plans often allow 90 to 180 days, and Medicaid plans run anywhere from 90 to 365. Miss it and you’ll see CO-29. That’s usually a write-off, because you can’t bill a timely-filing denial to the patient and you can’t just re-bill it.
The Basics
What “Timely Filing” Means
Timely filing is the maximum amount of time a payer allows between the date of service and the day a clean claim lands in their system. Every insurer sets its own window. Submit one day past the limit and the claim comes back denied, typically with remittance advice code CO-29, “the time limit for filing has expired.”
The painful part is what happens next. You usually can’t bill a timely-filing denial to the patient, and you can’t just re-bill it to recover the money. Unless you can prove the claim went in on time, that session is a write-off, and there’s no appeal on the merits of the care, only on whether the filing deadline was met.
Behavioral health practices carry more timely-filing risk than most specialties. Care runs as recurring weekly or biweekly sessions, so one broken workflow can bury dozens of claims at once. Where a medication or Spravato needs an authorization, it can expire and get re-requested mid-treatment. And every claim has to survive the trip from the EHR to the clearinghouse to the payer, a chain where claims regularly stall and nobody notices until it’s past the deadline. Catching those patterns early is a big part of what revenue cycle management is for.
Deadlines
Typical Filing Limits By Payer
Filing limits come from your contracts, not one national rule, so treat the figures below as common ranges. They aren’t guarantees for your specific plans. Confirm the exact window in your participating-provider agreement or the payer’s provider manual before you rely on it.
| Payer type | Typical initial filing limit |
|---|---|
| Medicare (Part B) | 12 months from the date of service |
| Medicaid / state plans | Varies widely, commonly 90 to 365 days |
| TRICARE | 12 months from the date of service |
| Commercial / BCBS | Often 90 to 180 days (some plans allow 365) |
| Corrected / resubmitted claims | Frequently shorter: 60 to 180 days from the determination |
Root Causes
Why Claims Miss The Deadline
A timely-filing write-off almost never comes from one late claim; it comes from a gap in the system, where claims slip out of view until the clock’s already run out. These are the usual culprits.
Front-End Delays
Charges that sit uncoded, intake errors, or unverified eligibility hold claims back at the source. By the time the front-end queue clears, a shorter commercial window may already be closing.
Authorization Waiting
Teams often hold claims while they wait on a prior authorization or a retro-auth, which in behavioral health mostly means medications and Spravato. Those auths can lapse and get re-requested mid-treatment, and every day of waiting comes straight out of the filing limit.
Rejections That Sit
A clearinghouse rejection isn’t a denial. It means the claim never reached the payer. Let a rejected claim sit unworked and the corrected version can blow past the original deadline, and the payer counts it as never filed.
EHR-To-Clearinghouse Gaps & COB Clock
Some claims never make it from the EHR to the clearinghouse, and nobody sees an error. They just never transmit. Secondary claims add their own risk, since the coordination-of-benefits clock can run out while you’re waiting on the primary payer’s remittance.
Prevention
How To Protect Every Deadline
Preventing timely-filing write-offs is a discipline. You don’t fix it once. A practice that submits on a predictable rhythm and watches its aging closely rarely loses money to CO-29, so build these habits into your weekly workflow.
- Track each payer’s filing limit in one reference your billing team uses, not buried in individual contracts.
- Send your claims on a set schedule (daily or several times a week) so nothing waits in a batch for weeks.
- Work clearinghouse rejections within 48 hours, while there’s still runway to correct and resubmit before the deadline.
- Track authorizations separately from claims so an expired or pending auth never silently parks a claim.
- Run an aging report that flags claims approaching their filing limit, and prioritize those first.
- Keep proof of timely submission for every claim: the acceptance reports and acknowledgment numbers you’ll need if a denial is wrong.
Many of these same controls prevent the slow buildup of unbilled and unpaid claims. If write-offs are already mounting, our breakdown of what causes an A/R backlog covers the upstream problems worth fixing first.
Recovery
Appealing A CO-29 Denial
Not every timely-filing denial is final. If you can show the claim went in on time, or that the payer caused the delay, you can appeal, but only within the payer’s defined appeal window. Your appeal is only as strong as the proof you kept. Gather it before you file.
Clearinghouse Acceptance Report
Your 277CA acceptance report shows the payer received and accepted the claim on a specific date. This is often the single most persuasive piece of evidence in a timely-filing appeal.
Payer Acknowledgment Number
A claim acknowledgment or trace number from the payer ties the original submission to a date inside the filing window, even if the claim was later lost on their end.
Dated Submission Logs
Time-stamped logs from your EHR or clearinghouse establish a paper trail of when each claim left your system, which is exactly what the appeal reviewer is checking.
Documentation Of Payer Error
If the delay was the payer’s fault (an eligibility system outage, a misrouted claim, wrong coordination-of-benefits info), document it, because a payer-caused delay is a recognized basis for overriding the limit.
A steady appeal routine pays off well beyond timely filing. Pair this with a repeatable denial management workflow so every denial type gets worked the same way, and lean on our denial follow-up worksheet to keep the proof and deadlines organized.
If claims on your aging report are already close to their limits, this is work we take on. Billing Cleanup And A/R Recovery works unpaid claims older than 90 days for 20% of what we collect, and you owe nothing on claims we don’t collect. If you’d rather hand off billing altogether, Ongoing Billing puts the whole cycle on us, priced by practice size, and our mental health billing services page shows what it covers. See medical billing prices by practice size.
FAQ
Frequently Asked Questions
What Is The Timely Filing Limit For Medicare?
Medicare Part B generally requires claims to be filed within 12 months (one calendar year) of the date of service. File late and the claim’s denied. It usually can’t be paid, either. For edge cases and exceptions, your Medicare Administrative Contractor has the current rules.
Can A Patient Be Billed For A Timely-Filing Denial?
In most cases, no. When a claim’s denied as CO-29 because the practice missed the filing deadline, the patient typically can’t be held responsible, and the amount becomes a provider write-off. Your payer contract has the final say, so check it before you balance-bill anyone.
Does A Clearinghouse Rejection Count As Timely Filing?
No. A clearinghouse rejection means the claim never reached the payer, so the payer doesn’t consider it filed at all. The filing clock keeps running until a clean claim is accepted, which is why working rejections within 48 hours matters so much.
How Do I Prove A Claim Was Filed On Time?
Keep your clearinghouse 277CA acceptance report, the payer’s claim acknowledgment or trace number, and dated submission logs from your EHR or clearinghouse. Together these establish the submission date inside the filing window and form the backbone of a timely-filing appeal.
What Would Fixing It Cost?
Ongoing Billing, Automation Programs and the Operations Partnership each have a published price and a written scope. Tell us what keeps going wrong, and we’ll point you to the right one.