Timely filing denials are the most avoidable category of lost revenue in medical billing. There is nothing clinically wrong with the claim. The service was legitimate, the coding was correct, the patient was covered. The payer simply received the claim after their deadline, and the denial is almost always final.
Every payer sets its own timely filing limit, and those limits vary significantly. Medicare gives you 12 months. Some commercial payers give you 90 days. A few give you as little as 60 days from the date of service. If your billing team does not have these limits memorized or readily accessible, you are at permanent risk of writing off revenue that was legitimately earned.
This reference page covers the timely filing limits for Medicare, Medicaid programs across your key states, and the major commercial payers your practice is most likely to bill. For the denial code that appears when a claim misses the deadline, see our dedicated guide: CO-29 Denial Code: Timely Filing Expired.
What Is a Timely Filing Limit?
A timely filing limit is the deadline by which a claim must be received by the payer after the date of service. If the claim arrives after this deadline, the payer issues a timely filing denial under Claim Adjustment Reason Code CO-29, and in most cases the revenue is permanently lost.
The deadline is measured from the date of service, not the date you submitted the claim. A claim submitted on day 89 of a 90-day window that is delayed in the clearinghouse and arrives on day 91 is still a timely filing denial. The payer’s received date controls, not your submission date.
This is why clearinghouse confirmation reports matter so much. When you submit a claim, your clearinghouse should return an acknowledgment with a timestamp. That report is your proof of timely filing the document you submit with an appeal if the payer wrongly denies a claim that was submitted within the window.
Timely Filing Limits -Complete Reference Table (2026)
Verify these limits directly with each payer before using them as the basis for an appeal. Payers can and do update their filing policies, and limits sometimes differ by plan type, line of business, or state.
GOVERNMENT PAYERS
| Payer | Filing Limit | Notes | Verify |
| Medicare (Part A and B) | 12 months | 365 days from date of service. Per CMS Claims Processing Manual Chapter 1, Section 70. Late filing exception available for certain administrative errors. | CMS.gov |
| Medicare Advantage (Part C) | 12 months | Must match traditional Medicare filing window per CMS requirements. Individual plan may apply stricter limits — verify with plan. | Plan EOC |
| Medicaid — New York (eMedNY) | 90 days | 90 days from date of service for most services. Extended limits apply for crossover claims and coordination of benefits situations. | eMedNY portal |
| Medicaid — Texas (TMHP) | 95 days | 95 days from date of service per TMHP billing guidelines. Extended limit of 365 days for crossover claims. | TMHP.com |
| Medicaid — California (Medi-Cal) | 6 months | 180 days from date of service per DHCS billing guidelines. Exceptions apply for retroactive eligibility determinations. | DHCS.ca.gov |
| Medicaid — New Jersey (NJ FamilyCare) | 180 days | 180 days from date of service. Extended to 365 days for claims involving third-party liability. | NJ DHS portal |
| Medicaid — Nevada | 12 months | 365 days from date of service for Nevada Medicaid fee-for-service claims. | DHCFP portal |
| Medicaid — Washington (Apple Health) | 12 months | 365 days from date of service. Exceptions allowed for specific administrative and eligibility-related delays. | HCA.wa.gov |
| TRICARE | 12 months | 365 days from date of service for civilian providers. Claims for active-duty servicemembers have extended windows. | TRICARE.mil |
COMMERCIAL PAYERS
| Payer | Filing Limit | Notes | Verify |
| UnitedHealthcare (UHC) | 90 days | 90 days from date of service for most commercial plans. Some employer plans specify 180 days confirm at the plan level, not just the payer level. | UHCprovider.com |
| Aetna | 180 days | 180 days from date of service for most Aetna commercial plans. Some self-funded employer plans use 90 days always verify against the specific plan. | Aetna.com |
| Anthem Blue Cross Blue Shield | 90 to 180 days | Varies by state and plan type. California, New York, and New Jersey plans commonly use 180 days. Verify against the specific Anthem plan documents. | Anthem portal |
| Cigna | 90 days | 90 days from date of service for most Cigna commercial plans. Cigna’s provider manual specifies the limit may differ for behavioral health claims. | CignaforHCP.com |
| Humana | 180 days | 180 days from date of service for most Humana commercial plans. Medicare Advantage plans follow the 365-day Medicare window. | Humana.com |
| Blue Shield of California | 180 days | 180 days from date of service. Applies to both commercial and Medi-Cal managed care plans. | blueshieldca.com |
| Health Net (California) | 180 days | 180 days from date of service for commercial plans. Health Net Medi-Cal managed care follows DHCS billing guidelines. | healthnet.com |
| Molina Healthcare | 180 days | 180 days from date of service across most Molina Medicaid managed care plans. Varies by state verify with the specific state plan. | molinahealthcare.com |
| Oscar Health | 180 days | 180 days from date of service per Oscar provider manual. | Oscar portal |
| Centene (Ambetter, WellCare) | 180 days | 180 days for most Centene subsidiary plans. Applies across Ambetter (Marketplace) and WellCare (Medicaid) lines. | Plan portal |
| Kaiser Permanente | 180 days | 180 days from date of service. Kaiser operates a closed network most claims are internal, but contracted non-Kaiser providers should verify by region. | KP portal |
| Important: These Limits Can Change and Vary by Plan The limits above reflect standard published guidelines for each payer as of 2026. Many large payers administer hundreds of self-funded employer plans, each of which can specify a different timely filing window in the plan documents. The limit printed on the patient’s insurance card or confirmed at eligibility verification may differ from the payer’s standard published limit. Always verify the timely filing limit at the plan level before using this table as the basis for an appeal. Source: CMS Claims Processing Manual, state Medicaid billing guidelines, and payer provider manuals. |
How Timely Filing Limits Are Measured
Date of Service vs. Date of Claim Receipt
The timely filing clock starts on the date of service, not the date you generated the claim or the date your clearinghouse submitted it. The clock stops on the date the payer receives the claim. A one-day delay in the clearinghouse pipeline during a high-volume period is enough to push a borderline claim past the deadline.
For services that span multiple dates inpatient admissions, therapy series, or recurring services most payers measure the filing window from the last date of service on the claim, not the first. Confirm this with each payer, because some measure from the first date of service on multi-date claims.
Coordination of Benefits and Secondary Claims
When a patient has two insurance plans, the timely filing clock for the secondary payer typically starts on the date the primary payer processes the claim, not the original date of service. This gives practices additional time to submit secondary claims after receiving the primary payer’s EOB, but the specific window varies by payer.
Most secondary payers allow 6 to 12 months from the primary payer’s payment date for secondary claim submission. Verify this directly with the secondary payer before submitting, particularly for Medicare secondary payer (MSP) situations where CMS rules govern the timeline.
Retroactive Eligibility and Late Enrollment
When a patient is retroactively enrolled in a plan a common situation with Medicaid, where eligibility may be confirmed weeks or months after the date of service — most payers allow the filing window to run from the date the provider received confirmation of coverage, rather than from the date of service. Document the date you received eligibility confirmation and keep it with the claim file.
Timely Filing Exceptions: When the Deadline Can Be Extended
Most payers include a timely filing exception process that allows late claims to be accepted under specific circumstances. The exceptions are narrow and require documentation, but they are worth pursuing when the delay was caused by a factor outside the practice’s control.
Payer or Clearinghouse System Error
If the payer’s system or your clearinghouse experienced a documented outage or processing error during the filing window, most payers will accept the claim with a late filing exception request. Keep your clearinghouse submission reports for every claim they are the primary evidence for this exception. The report should show the claim was submitted within the filing window even if it was not received in time due to a system issue.
Administrative Error by the Payer
If the payer previously denied the claim for a different reason (wrong insurance ID, missing information, coding error) and you corrected and resubmitted within the corrected claim’s own filing window, the resubmission timely filing window typically runs from the date of the original denial, not the original date of service. Document all prior denial dates and resubmission dates.
Retroactive Insurance Notification
When the practice was not informed of a patient’s insurance coverage until after the original filing deadline passed, most payers allow a late filing exception with documentation showing the date the practice received insurance information.
Natural Disaster or Federal Emergency Declarations
CMS issues automatic timely filing extensions during federal emergency declarations. During the COVID-19 public health emergency, for example, CMS extended Medicare timely filing deadlines for affected providers. Monitor CMS emergency policy updates for any active extensions that apply to your claims.
How to Appeal a CO-29 Timely Filing Denial
If you receive a CO-29 denial and you have documentation that the claim was submitted within the filing window, a timely filing appeal is straightforward. Here is what to include:
- The clearinghouse acknowledgment report showing the claim submission timestamp within the filing window
- The original claim number and date of service
- The payer’s published timely filing limit and the source document (provider manual, state Medicaid billing guide, or payer website)
- A cover letter stating specifically: ‘This claim was submitted within the timely filing window. Proof of timely submission is attached. We request this denial be reversed and the claim reprocessed.’
The appeal window for CO-29 is the same as for any other denial typically 60 to 180 days from the denial date, depending on the payer. Do not miss the appeal window on top of the filing window. If you have valid proof of timely submission, most payers will reverse the CO-29 denial upon receipt of the clearinghouse report.
Preventing Timely Filing Denials
The best timely filing strategy is never getting close to the deadline in the first place.
- Submit claims within 3 to 5 business days of service not at the end of the month, not in weekly batches. Daily submission cycles eliminate timely filing risk entirely for standard service windows.
- Set practice management system alerts at 30 days of no response on any submitted claim. A claim sitting without a payer response after 30 days may not have been received.
- Never let a claim sit unworked past 60 days regardless of the payer’s filing window.
- Keep clearinghouse submission reports for every claim for the duration of the payer’s filing window plus 90 days.
- Verify the filing limit for every payer you bill at the plan level, not just the payer level. Self-funded employer plans can specify shorter windows in their plan documents.
- For corrected claims and resubmissions, track the resubmission date and the applicable timely filing window separately from the original claim.
| Prevention Protocol Timely Filing Daily claim submission cycle: submit all charges within 3 to 5 business days of service 30-day alert: flag any submitted claim with no payer response after 30 days 60-day hard stop: no claim sits unworked past 60 days Clearinghouse report archive: retain submission acknowledgments for each claim Payer-specific limit log: maintain a current list of filing deadlines for every payer you bill, updated annually Resubmission tracking: track corrected claim dates and their own timely filing windows separately |
Managing Timely Filing Across a Multi-Payer Practice
For a practice billing Medicare, Medicaid, and five or more commercial payers, managing different timely filing windows without a systematic approach is genuinely difficult. The windows range from 90 days to 12 months. Employer-sponsored plans can differ from the payer’s standard window. Corrected claims have their own timeline. Secondary claims run on a different clock from primary claims.
The practices that eliminate timely filing denials entirely share one habit: daily claim submission with a 30-day follow-up protocol. Claims submitted daily and followed up at 30 days of silence never get close to any payer’s deadline. If your practice is still running weekly or monthly billing cycles, that habit alone is generating avoidable CO-29 write-offs every month.
If you want help identifying where your current billing cycle is leaving timely filing exposure, schedule a free denial analysis with Globill Medical Resources LLC. We will pull your CO-29 denial volume, identify which payers and service dates are generating them, and show you exactly where the billing cycle needs to tighten up.
