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 from 90 to 365. Miss it and you’ll see CO-29, usually a write-off, since you can’t bill the patient for a timely-filing denial or simply re-bill it.
The Basics
What “Timely Filing” Means
Timely filing is the maximum time a payer allows between the date of service and a clean claim landing in their system. Submit one day late and the claim is denied, typically with remittance advice code CO-29, “the time limit for filing has expired.”
You usually can’t bill the patient for a timely-filing denial or simply re-bill it to recover the money. Unless you can prove on-time filing, the session is a write-off, and any appeal turns only on the deadline, not the care.
Behavioral health carries more timely-filing risk than most specialties. Recurring weekly or biweekly sessions mean one broken workflow can bury dozens of claims at once, and an authorization for a medication or Spravato can expire and get re-requested mid-treatment.
Every claim must also survive the trip from the EHR to the clearinghouse to the payer, where claims stall unnoticed until the deadline’s past. Catching those patterns early is what revenue cycle management is for.
Deadlines
Typical Filing Limits By Payer
Filing limits come from your contracts, not one national rule, so treat these as common ranges, not promises for your plans. Confirm the exact window in your participating provider agreement or the payer’s provider manual.
| 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 where claims slip out of view until the clock runs out.
Front-End Delays
Charges that sit uncoded, intake errors, or unverified eligibility hold claims back at the source. By the time the queue clears, a shorter commercial window may be closing.
Authorization Waiting
Teams often hold claims while waiting on a prior authorization or retro auth, which in behavioral health mostly means medications and Spravato. Auths can lapse and get re-requested mid-treatment, and every day of waiting comes out of the filing limit.
Rejections That Sit
A clearinghouse rejection isn’t a denial; the claim never reached the payer. Left unworked, the corrected version can blow past the deadline and count as never filed.
EHR To Clearinghouse Gaps & COB Clock
Some claims never make it from the EHR to the clearinghouse, with no error shown. Secondary claims add risk, since the coordination-of-benefits clock can run out while you wait on the primary payer’s remittance.
Prevention
How To Protect Every Deadline
Preventing write-offs is ongoing discipline. 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.
- Keep each payer’s filing limit in one reference your billing team uses, not buried in contracts.
- Send 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 time 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 nearing their filing limit, and work those first.
- Keep proof of timely submission for every claim: the acceptance reports and acknowledgment numbers you’d need to dispute a wrong denial.
Many of these controls also 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 to fix 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 appeal window. Your appeal is only as strong as the proof you kept, so gather it before you file.
Clearinghouse Acceptance Report
Your 277CA acceptance report shows the payer received and accepted the claim on a specific date, often the most persuasive 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 they later lost the claim.
Dated Submission Logs
Time-stamped logs from your EHR or clearinghouse show when each claim left your system, which is exactly what the appeal reviewer checks.
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 payer-caused delay is a recognized basis for overriding the limit.
Pair a steady appeal routine with a repeatable denial management workflow so every denial type gets worked the same way, and use our denial follow-up worksheet to keep proof and deadlines organized.
If claims on your aging report are close to their limits, we take that work 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. To 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 filing within 12 months (one calendar year) of the date of service. File late and the claim’s denied and usually can’t be paid. Your Medicare Administrative Contractor has the current rules for exceptions.
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 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 acknowledgment or trace number, and dated submission logs from your EHR or clearinghouse. Together they establish the submission date inside the filing window and anchor a timely-filing appeal.