Claim Filing Deadline Checker
Free Tool
Calculate exact claim filing deadlines by payer — with state Medicaid lookup, secondary EOB trigger, retro eligibility flags, and contract overrides. Avoid CO-29 denials.
Step 1 — Enter claim details
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📌 When provided, the secondary claim deadline is calculated from the primary payer’s EOB date, not the DOS. Leave blank to use the DOS-based 180-day estimate.
⚡ Special Circumstances retro eligibility · contract override
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Enter the contracted filing limit from your signed provider agreement. Leave blank to use the standard payer window.
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⚡ Retroactive Eligibility Exception Applied
CO-29 Denial Warning
This claim’s timely filing deadline has passed. Submitting now will likely result in a CO-29 denial. You may still appeal with documented proof of prior timely submission — clearinghouse confirmation, EHR audit log, or certified mail receipt timestamped before the deadline.
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📋 Corrected claim deadline
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📄 Secondary claim
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⚑ Appeal window
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🚫 CO-29 appeal status
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Batch mode — paste multiple dates of service (one per line, MM/DD/YYYY format) or upload a CSV. Select a payer and claim type for the entire queue. Results are color-coded by urgency and sortable.
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Drop a CSV here or click to browse
First column = date (MM/DD/YYYY). Headers optional.
Sort by:
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📋 Medical Billing Guide · Updated June 2026
Timely Filing Limits in Medical Billing: The Complete 2026 Guide to Avoiding CO-29 Denials
CO-29 is the most preventable denial in revenue cycle management — and it costs U.S. practices billions every year. This guide covers every major payer's timely filing window, state Medicaid deadlines, CO-29 appeal strategy, and the workflows that stop deadline denials before they start.
Medical Billing Compliance Notice: This article is for educational and informational purposes only. Filing deadlines and payer policies change frequently. Always verify current timely filing requirements with your specific provider contract, payer portal, or contracted billing representative before submitting claims. CureAdvantage is not a law firm and this content does not constitute legal or financial advice.
Every day, U.S. medical practices write off millions of dollars in reimbursements that were legitimately owed — not because the services weren't documented, not because the codes were wrong, but because the claim arrived one day late.
The culprit is a timely filing denial, coded as CARC CO-29: "The time limit for filing has expired." Unlike most denial categories — undercoding, missing modifiers, eligibility mismatches — a CO-29 denial is almost always permanent. Once the deadline passes, your only recourse is a documented proof-of-timely-submission appeal. If you have no proof, the revenue is gone.
$262B
Lost annually to billing errors & missed deadlines in U.S. healthcare
~12%
Average initial claim denial rate across major commercial payers (HFMA, 2024)
65%
Of denied claims are never reworked or resubmitted
This guide is written for medical billers, practice managers, and revenue cycle directors who need authoritative, actionable information on timely filing limits — with every major payer's current window, state Medicaid deadlines, and a step-by-step CO-29 appeal framework.
What Is a Timely Filing Limit in Medical Billing?
A timely filing limit (also called a timely filing deadline or filing window) is the maximum number of calendar days a healthcare provider has to submit a claim to an insurance payer after the date of service (DOS). Once this window closes, the payer is contractually and legally permitted to deny the claim as untimely, regardless of whether the service was clinically appropriate and correctly coded.
Timely filing limits are set by:
- Federal law — for Medicare (42 CFR §424.44 mandates a 12-month window for Part A and B)
- State Medicaid regulations — each state's Medicaid program sets its own deadline, ranging from 90 days (New York) to 365 days
- Commercial payer contracts — written into your provider participation agreement and subject to change at contract renewal
💡 Critical Distinction
The timely filing limit is not the same as the claims processing timeline. A claim submitted on day 89 of a 90-day window is timely — even if it takes 30 more days to process. What matters is the submission date, documented by a clearinghouse confirmation timestamp.
For most commercial payers, the filing window is buried on page 40 of your provider manual or in a contract addendum. Many practices discover their contracted deadline only after receiving a CO-29 denial — by then, the revenue may already be unrecoverable.
What Is a CO-29 Denial Code?
CO-29 is a Claim Adjustment Reason Code (CARC) published by X12 and used across all Medicare, Medicaid, and commercial payer Explanations of Benefits (EOBs). CO stands for "Contractual Obligation" — meaning the denial is based on a contract-level provision, not clinical judgment. The full descriptor is:
"The time limit for filing has expired."
— CARC CO-29, X12 Claim Adjustment Reason Code Committee
CO-29 is unique in the denial landscape because it is almost never overturned without documented proof of prior timely submission. A clinical justification, a corrected code, or an authorization number cannot cure a CO-29 — only evidence that the original claim was in the payer's hands before the deadline.
CO-29 vs. CO-97: Know the Difference
Billers sometimes confuse CO-29 with CO-97 (service not covered by benefit category) or CO-4 (service not covered by this type of plan). CO-29 is specifically and exclusively a timely filing denial. If you are seeing CO-29 on a claim you know was submitted on time, the issue is documentation — you need to locate your clearinghouse acknowledgment and file a proof-of-timely-submission appeal.
🚫 Do Not Bill the Patient for CO-29 Denials
Under most provider agreements and state law, timely filing denials are a provider-side administrative failure. You cannot shift a CO-29 write-off to the patient unless your contract explicitly permits it, which is rare. Billing patients for uncollectable CO-29 amounts may violate your payer agreement and state balance billing regulations.
Timely Filing Limits by Major Payer (2026)
The table below reflects current payer filing windows as of June 2026. Filing limits can change at contract renewal — always verify against your current provider agreement. Use the Claim Filing Deadline Checker above to calculate your exact deadline and days remaining for any payer.
| Payer / Plan | Network / Plan Type | Filing Window | Clock Starts | Notes & Warnings |
|---|---|---|---|---|
| Government & Federal Programs | ||||
| Medicare Part A | All providers (inpatient) | 365 days | Date of service / discharge | Per 42 CFR §424.44. Inpatient facility claims measured from discharge date. |
| Medicare Part B | All providers (outpatient) | 365 days | Date of service | Per 42 CFR §424.44. Late filing requires documented good cause exception. |
| Medicare Part B – Late Charges | Facility outpatient | 365 days | Original claim payment date | Late charges on UB-04 must be filed within 365 days of original claim payment. |
| Medicare Secondary Payer (MSP) | Medicare as secondary | Up to 3 years | Primary EOB date or DOS | Extended MSP window under 42 CFR §489.20. Requires primary EOB documentation. |
| TRICARE / CHAMPUS | All (Active duty & dependents) | 365 days | Date of service | Standard across most TRICARE plans. TRICARE for Life: 1 year from DOS or primary EOB. |
| TRICARE for Life (TFL) | Medicare-eligible beneficiaries | 365 days | Primary EOB date | TFL is always secondary to Medicare. Clock starts from Medicare EOB date. |
| CHAMPVA | Veterans' dependents | 365 days | Date of service | Managed by VA. 1-year standard. Up to 2 years if other insurance is involved. |
| VA Community Care | Authorized community providers | 180 days | Date of service | 180-day window for VA-authorized community care claims. Submit via Optum or TriWest. |
| Indian Health Service (IHS) | Tribal & IHS facilities | 365 days | Date of service | Follows federal Medicaid rules for crossover claims. Verify with IHS fiscal intermediary. |
| FEHB – Federal Employees | All federal employees | 90–365 days | Date of service | Varies by individual FEHB carrier plan. Blue Cross FEP: 365 days. Others: 90–180 days. |
| Medicaid (federal baseline) | All Medicaid beneficiaries | 365 days (est.) | Date of service | Federal baseline. Individual states may use shorter windows — see full state table below. |
| Medicare Advantage (Part C) Plans | ||||
| Aetna Medicare Advantage | HMO / PPO / PFFS | 120 days | Date of service | Both original and resubmitted claims. Verify with Aetna Medicare provider portal. |
| Anthem Medicare Advantage | HMO / PPO | 90–180 days | Date of service | Varies by region and plan type. 180 days is common. Verify local Anthem MA contract. |
| Bright Health Medicare Advantage | HMO | 90 days | Date of service | Tight window. Electronic submission strongly preferred. |
| Centene / WellCare Medicare Advantage | HMO / SNP | 90–180 days | Date of service | Varies by plan and state. 90 days standard for most WellCare MA plans. |
| Cigna Medicare Advantage | HMO / PPO | 120 days | Date of service | 120-day standard. Verify your specific CMS contract year agreement. |
| Devoted Health | HMO | 90 days | Date of service | 90-day window. Devoted is fast-growing in southeastern and midwestern markets. |
| EmblemHealth Medicare Advantage | HMO | 90 days | Date of service | Primarily New York market. Verify with EmblemHealth provider relations. |
| Highmark Medicare Advantage | HMO / PPO | 180 days | Date of service | BCBS affiliate. 180-day standard across most Highmark MA plans. |
| Humana Medicare Advantage | HMO / PPO / PFFS | 90 days | Date of service | One of the largest MA payers. Strict 90-day window — file early. |
| Kaiser Permanente Medicare Advantage | HMO | 90 days | Date of service | HMO model. All services must be referred/authorized through Kaiser network. |
| Molina Medicare Advantage | HMO / SNP | 90 days | Date of service | SNP (Special Needs Plans) for dual eligibles. 90-day window standard. |
| SCAN Health Plan (Medicare Advantage) | HMO | 90 days | Date of service | California, Nevada, Arizona, Texas market. Verify with SCAN provider portal. |
| UnitedHealthcare Medicare Advantage | HMO / PPO / PFFS | 90 days | Date of service | Largest MA plan by enrollment. Some plan variants extend to 180 days — verify contract. |
| BCBS Medicare Advantage (local plans) | HMO / PPO | 90–180 days | Date of service | Varies significantly by state BCBS plan. Always verify with your local plan's provider manual. |
| Commercial Payers (Employer-Sponsored & Individual Market) | ||||
| Aetna – Participating | In-network / participating | 90 days | Date of service | Electronic preferred. Verify at Availity or Aetna provider portal. Some group contracts differ. |
| Aetna – Non-Participating | Out-of-network | 180 days | Date of service | Standard out-of-network provision for commercial plans. |
| Ambetter (Centene) | Marketplace / ACA plans | 90–180 days | Date of service | ACA marketplace plan. Varies by state. 90 days is common — verify local Centene contract. |
| AmeriHealth | Commercial HMO / PPO | 180 days | Date of service | Mid-Atlantic market (PA, NJ, DE). Verify with AmeriHealth provider manual. |
| Anthem – Commercial | All commercial plan types | 180 days | Date of service | Anthem is the BCBS licensee in 14 states. Some employer groups may have 90-day contracts. |
| BCBS Alabama | HMO / PPO / BlueCard | 365 days | Date of service | One of the more generous BCBS plans. Verify with Alabama BCBS provider manual. |
| BCBS Arizona | HMO / PPO | 180 days | Date of service | Standard AZ BCBS commercial window. Verify current provider agreement. |
| BCBS California (Anthem) | HMO / PPO | 90–180 days | Date of service | Anthem administers BCBS in CA. Employer group contracts may specify 90 days. |
| BCBS Federal Employee Program (FEP) | Federal employees | 365 days | Date of service | One of the longest commercial windows. All FEP members nationwide under this plan. |
| BCBS Florida (Florida Blue) | HMO / PPO / EPO | 180 days | Date of service | Florida Blue standard commercial window. |
| BCBS Illinois / HCSC | HMO / PPO | 90–180 days | Date of service | HCSC administers BCBS in IL, MT, NM, OK, TX. Verify plan-specific contract terms. |
| BCBS Michigan | HMO / PPO / BCN | 180 days | Date of service | Blue Care Network (HMO) and Blue Cross commercial PPO each have their own provider manuals. |
| BCBS North Carolina | HMO / PPO / Blue Local | 180 days | Date of service | Standard NC BCBS commercial window. |
| BCBS Texas (HCSC) | HMO / PPO | 90–180 days | Date of service | HCSC-managed. Some large employer group plans specify 90 days — always verify contract. |
| Cigna – In-Network | Participating | 90–180 days | Date of service | Cigna uses 90-day windows for many contracts; 180 days is standard for most commercial plans. |
| Cigna – Out-of-Network | Non-participating | 180 days | Date of service | Standard OON commercial provision. |
| Coventry Health Care | HMO / PPO (now Aetna) | 90–180 days | Date of service | Now administered as Aetna. Legacy Coventry plans still active in some markets — treat as Aetna. |
| Dean Health Plan | HMO (Wisconsin) | 90 days | Date of service | Wisconsin-based. Tight 90-day window. Electronic submission only. |
| EmblemHealth – Commercial | HMO / GHI / HIP | 90 days | Date of service | Primarily New York market (GHI & HIP brands). 90-day standard for most plans. |
| Friday Health Plans | ACA Marketplace | 90 days | Date of service | Multi-state ACA plan. 90-day window. Verify current operational status with state DOI. |
| Geisinger Health Plan | HMO / PPO (Pennsylvania) | 90 days | Date of service | Pennsylvania-based regional plan. 90-day standard. |
| Harvard Pilgrim Health Care | HMO / PPO (New England) | 180 days | Date of service | Now part of Point32Health with Tufts. 180-day standard for most commercial plans. |
| Health Net – Commercial | HMO / PPO (West Coast) | 90 days | Date of service | Centene subsidiary. CA, AZ, OR, WA markets. 90-day standard. |
| Highmark Blue Shield (PA) | HMO / PPO / EPO | 180 days | Date of service | BCBS licensee for western PA and WV. Verify with Highmark provider portal. |
| Humana – Commercial | HMO / PPO / EPO | 90 days | Date of service | Employer-sponsored and individual plans. 90-day strict window across most commercial lines. |
| Independence Blue Cross (IBX) | HMO / PPO / Keystone | 180 days | Date of service | Philadelphia-area BCBS affiliate. 180-day standard commercial window. |
| Kaiser Permanente – Commercial | HMO (closed network) | 90 days | Date of service | Closed HMO model. Non-Kaiser providers require prior authorization — verify before billing. |
| Magellan Health – Behavioral | Behavioral health carve-out | 180 days | Date of service | Behavioral and mental health carve-out plans. 180-day standard. Now part of Centene. |
| Medica Health Plans | HMO / PPO (Midwest) | 90 days | Date of service | Minnesota, Wisconsin, Iowa, Nebraska, North & South Dakota market. |
| Medical Mutual of Ohio | HMO / PPO | 180 days | Date of service | Ohio-based commercial carrier. 180-day standard window. |
| Molina Healthcare – Commercial | Marketplace / Exchange | 180 days | Date of service | ACA marketplace and state exchange plans. 180-day standard across most Molina commercial lines. |
| MultiPlan / PHCS | Network rental (out-of-network) | 90–180 days | Date of service | MultiPlan is a network rental — follow the underlying payer's filing deadline, not MultiPlan's. |
| MVP Health Care | HMO / PPO (Northeast) | 90 days | Date of service | New York and Vermont market. 90-day standard. Verify with MVP provider portal. |
| Oscar Health | HMO / EPO (ACA marketplace) | 90 days | Date of service | Multi-state ACA carrier. 90-day window — submit claims promptly via Oscar's provider portal. |
| Point32Health (Tufts Health) | HMO / PPO (New England) | 180 days | Date of service | Tufts Health Plan and Harvard Pilgrim combined entity. 180-day standard. |
| PreferredOne (MN) | HMO / PPO (Minnesota) | 90 days | Date of service | Regional Minnesota plan. 90-day window. Electronic billing required. |
| Priority Health (MI) | HMO / PPO (Michigan) | 90 days | Date of service | Michigan-based. 90-day window. Verify at Priority Health provider portal. |
| Regence BlueCross BlueShield | HMO / PPO (Pacific NW) | 180 days | Date of service | OR, WA, ID, UT markets. 180-day standard commercial window. |
| Scott & White Health Plan (TX) | HMO (Texas) | 90 days | Date of service | Texas-based HMO. Now part of Baylor Scott & White. 90-day window. |
| SelectHealth (UT) | HMO / PPO (Intermountain) | 90–180 days | Date of service | Utah/Idaho/Nevada market. Intermountain Health affiliate. Verify specific plan window. |
| Sunshine Health (Centene) | Medicaid / Marketplace (FL) | 90–180 days | Date of service | Florida Medicaid managed care plan. Verify with Centene Florida provider manual. |
| UnitedHealthcare – In-Network | Participating / contracted | 90 days | Date of service | Largest commercial payer in the U.S. 90-day in-network standard. Some multi-site contracts differ. |
| UnitedHealthcare – Out-of-Network | Non-participating | 180 days | Date of service | Standard OON window. Some plans reduced to 90 days — always verify UHC provider agreement. |
| UnitedHealthcare Community Plan (Medicaid) | Medicaid managed care | 90–365 days | Date of service | Varies by state Medicaid contract. Follows state Medicaid filing window — see state table below. |
| WellPoint (now Elevance / Anthem) | Commercial / Marketplace | 180 days | Date of service | Rebranded to Elevance Health in 2022. Operates as Anthem in most markets. 180-day standard. |
| Centene / WellCare – Commercial | Marketplace / Exchange | Up to 365 days | Date of service | Varies by state. Most Centene/WellCare commercial plans use a 365-day window. |
| Specialty, Liability & Other Payers | ||||
| Workers' Compensation – General | Employer WC insurance | 90 days (varies) | Date of service / determination date | Varies significantly by state law. Many states require initial filing within 30–90 days. Always verify your state's WC regulations. |
| Auto / No-Fault (PIP) | Auto insurance / PIP | 30–90 days | Date of service | Among the tightest windows in billing. Many states (FL, NY, NJ) require PIP claims within 30 days of service. Confirm state-specific no-fault statute. |
| Liability / Third-Party (tort) | Personal injury / liability | Varies widely | Settlement / determination date | Governed by state statute of limitations, not payer contract. Typically 2–6 years from date of injury. Verify applicable state SOL. |
| Managed Medicaid – General | Medicaid MCO plans | Follows state Medicaid | Date of service | Managed Medicaid plans (UHC Community, Molina, Centene, etc.) follow the underlying state Medicaid filing window — see full state table below. |
| CHIP (Children's Health Ins. Program) | Children / families | 90–365 days | Date of service | Follows state Medicaid or CHIP-specific rules. Most states: 365 days. Verify by state. |
| Marketplace / ACA Exchange Plans | Individual & family plans | 90–180 days | Date of service | Varies by carrier operating on the exchange. Always verify with the specific insurer, not just the marketplace platform. |
| Short-Term Health Plans | Limited benefit plans | 30–90 days | Date of service | Non-ACA compliant plans with very tight filing windows. Treat as high-priority. Read each plan's EOC carefully. |
| Self-Funded / ASO Plans | Employer self-insured (ERISA) | 90–365 days | Date of service | Governed by the employer's Summary Plan Description (SPD), not state insurance law. ERISA pre-empts state balance billing laws. Verify SPD for exact window. |
⚠️ Medicare Advantage Is Not Medicare
A common and costly mistake: Medicare Advantage (Part C) plans are administered by private insurers and are not bound by the 365-day Medicare timely filing rule. A Medicare Advantage – UHC plan has a 90-day filing window — not 365 days. Always treat MA plans according to the individual plan's provider contract, not the Medicare fee-for-service standard.
State Medicaid Timely Filing Windows (2026)
While most states align with a 365-day Medicaid filing window, a handful impose significantly stricter deadlines that catch providers off guard. The table below highlights the states that deviate from the 365-day standard. Use the state Medicaid selector in the tool above to calculate your exact deadline for any state program.
| State | Medicaid Program Name | Filing Window | Notes |
|---|---|---|---|
| ⚠ Non-Standard Windows — Below 365 Days | |||
| 🔴 New York | NY Medicaid (eMedNY) | 90 days | Shortest Medicaid window in the U.S. Providers billing NY Medicaid must prioritize same-week submission from DOS. |
| 🔴 Texas | TMHP (Texas Medicaid & Healthcare Partnership) | 95 days | Second-shortest state window. TMHP enforces strictly. Submit within 2 weeks of DOS as a best practice. |
| 🟡 Illinois | Illinois Dept. of Healthcare & Family Services (HFS) | 180 days | Shorter than the federal standard. Verify with your Illinois Medicaid MAC or managed care plan. |
| 🟡 Indiana | Healthy Indiana Plan / Hoosier Healthwise (OMPP) | 180 days | 180-day window. Some Indiana managed Medicaid plans may impose different limits — verify your MCO contract. |
| 🟡 New Jersey | NJ FamilyCare (NJ DMAHS) | 180 days | 180-day window via NJ Division of Medical Assistance and Health Services fiscal agent. Verify with DXC Technology (NJ fiscal agent). |
| 🟢 Standard Windows — 365 Days (All Remaining States) | |||
| Alabama | Alabama Medicaid Agency | 365 days | 12-month standard window from DOS. Verify with Alabama Medicaid's Provider Reimbursement Manual. |
| Alaska | Alaska Medicaid (Division of Public Assistance) | 365 days | Federal standard. Electronic claims submitted through Conduent Alaska fiscal agent. |
| Arizona | AHCCCS (Arizona Health Care Cost Containment System) | 365 days | AHCCCS contracts with managed care plans — each MCO may have plan-level filing requirements. Verify with your specific AHCCCS MCO. |
| Arkansas | Arkansas Medicaid (DHS Division of Medical Services) | 365 days | Standard 12-month window. Arkansas Medicaid is administered through DXC Technology. |
| California | Medi-Cal (DHCS) | 365 days | Standard 12-month window from DOS. Retroactive eligibility situations may extend the effective window — document retro enrollment date. |
| Colorado | Colorado Medicaid (Health First Colorado) | 365 days | Health First Colorado standard 12-month window. Claims submitted via MMIS or managed care plan. |
| Connecticut | Connecticut Medicaid (HUSKY Health) | 365 days | HUSKY A, B, C, and D plans all follow the standard 365-day window. |
| Delaware | Delaware Medicaid (Diamond State Health Plan) | 365 days | Delaware's managed Medicaid plan (DSHP) follows standard 365-day window. |
| District of Columbia | DC Medicaid (DC Healthy Families / DC Alliance) | 365 days | DC Medicaid covers both citizens and non-qualifying immigrants under DC Alliance. Standard 365-day window. |
| Florida | Florida Medicaid (AHCA / Statewide Medicaid Managed Care) | 365 days | Florida uses managed care exclusively. Each SMMC plan (Humana, Molina, Sunshine, UHC, WellCare) may have specific timely filing requirements — verify with your plan. |
| Georgia | Georgia Medicaid (DCH / Gateway) | 365 days | Georgia Families 360° and PeachCare for Kids. CMOs (CareSource, Amerigroup, Peach State) follow 365-day standard. |
| Hawaii | Hawaii Medicaid (Med-QUEST Division) | 365 days | Med-QUEST is Hawaii's managed Medicaid program. Quest Integration plans follow the 365-day standard. |
| Idaho | Idaho Medicaid (Division of Medicaid) | 365 days | Idaho Medicaid uses both fee-for-service and managed care. Verify with Idaho MMIS or your MCO plan. |
| Iowa | Iowa Medicaid (Iowa Total Care / Molina / UHC) | 365 days | Iowa operates through managed care organizations. Each MCO (Iowa Total Care, Molina, UHC) follows the 365-day state standard. |
| Kansas | KanCare (Aetna, Sunflower Health, United) | 365 days | Kansas managed Medicaid through KanCare MCOs. All three managed care plans follow the 365-day standard. |
| Kentucky | Kentucky Medicaid (Managed Care / Passport Health) | 365 days | Kentucky Medicaid uses managed care through Aetna, Humana, Molina, UHC, and WellCare. All follow 365-day state standard. |
| Louisiana | Healthy Louisiana (Aetna, AmeriHealth, Humana, Molina, UHC) | 365 days | All five Healthy Louisiana Medicaid managed care plans follow the 365-day state standard. |
| Maine | MaineCare (Maine DHHS) | 365 days | Maine operates primarily fee-for-service Medicaid. Standard 365-day window. |
| Maryland | Maryland Medicaid (HealthChoice MCOs) | 365 days | Maryland's HealthChoice managed care program. MCOs (Aetna, CareFirst, Jai Medical, Priority Partners, UHC, Wellpoint) follow the 365-day state standard. |
| Massachusetts | MassHealth (EOHHS) | 365 days | MassHealth ACO and Managed Care plans follow the standard 365-day window. Massachusetts also has state-specific balance billing protections. |
| Michigan | Michigan Medicaid (Healthy Michigan Plan / MIChild) | 365 days | Michigan uses Medicaid Health Plans (MHPs). All MHPs follow the 365-day state standard. Verify with your specific MHP. |
| Minnesota | Medical Assistance / MinnesotaCare (DHS) | 365 days | Minnesota is primarily fee-for-service with some managed care. Standard 365-day window across all plan types. |
| Mississippi | Mississippi Medicaid (MississippiCAN / CHIP) | 365 days | Mississippi's managed Medicaid (MississippiCAN) through UHC and Molina. Both plans follow the 365-day state standard. |
| Missouri | MO HealthNet (Missouri Medicaid / MoMom) | 365 days | Missouri operates fee-for-service and managed care (Healthy Blue, Home State Health, UHC Community). All follow 365-day standard. |
| Montana | Montana Medicaid (DPHHS) | 365 days | Montana primarily fee-for-service. Standard 365-day window. Claims submitted via Conduent Montana fiscal agent. |
| Nebraska | Nebraska Medicaid (Heritage Health) | 365 days | Nebraska Heritage Health Program is managed Medicaid through UHC and WellCare. Both follow 365-day state standard. |
| Nevada | Nevada Medicaid (Nevada Check Up / Medicaid MCOs) | 365 days | Nevada Medicaid managed care through Aetna Better Health and SilverSummit (Centene). Both follow 365-day state standard. |
| New Hampshire | New Hampshire Medicaid (NH Healthy Families / WellSense) | 365 days | NH Medicaid managed care through NH Healthy Families (Centene) and WellSense (BCBS MA). Both follow 365-day state standard. |
| New Mexico | Centennial Care (NMHSD Medicaid) | 365 days | New Mexico Centennial Care managed through Molina, Presbyterian, UHC, and Western Sky (Centene). All follow 365-day standard. |
| North Carolina | NC Medicaid (NC Medicaid Direct / Tailored Plans) | 365 days | NC Medicaid transitioned to managed care in 2021. PHP and Standard Plan contractors follow 365-day state standard. Verify with your NC Medicaid PHP. |
| North Dakota | North Dakota Medicaid (DHS) | 365 days | North Dakota primarily fee-for-service. Standard 365-day window. Claims via DHS fiscal agent. |
| Ohio | Ohio Medicaid (OhioMHAS / ODM Managed Care) | 365 days | Ohio Medicaid redesigned in 2022 with a new managed care system. All OhioMHAS MCOs follow the 365-day state standard. |
| Oklahoma | SoonerCare / SoonerSelect (Oklahoma Medicaid) | 365 days | Oklahoma launched managed Medicaid (SoonerSelect) in 2023. MCOs (Aetna, Humana, Soonercare Health Plan, UHC) follow the 365-day state standard. |
| Oregon | Oregon Health Plan (OHP / CCO model) | 365 days | Oregon Health Plan operates through Coordinated Care Organizations (CCOs). Each CCO sets its own claims requirements — verify with your specific CCO. State standard: 365 days. |
| Pennsylvania | Pennsylvania Medical Assistance (MA / HealthChoices) | 365 days | Pennsylvania HealthChoices managed Medicaid through five zone contractors. All follow the 365-day state standard. |
| Rhode Island | RIte Care / Medicaid Managed Care (EOHHS) | 365 days | Rhode Island RIte Care managed by Neighborhood Health Plan and UHC Community. Both follow 365-day state standard. |
| South Carolina | Healthy Connections Medicaid (SCDHHS) | 365 days | South Carolina Healthy Connections managed care through Absolute Total Care (Centene) and Molina. Both follow the 365-day state standard. |
| South Dakota | South Dakota Medicaid (DSS) | 365 days | South Dakota primarily fee-for-service. Standard 365-day window. Claims submitted through DXC Technology fiscal agent. |
| Tennessee | TennCare (TENNCARE Bureau / Managed Care) | 365 days | TennCare managed through AmeriGroup (Elevance), BlueCare Tennessee, and UHC Community. All three follow 365-day state standard. |
| Utah | Utah Medicaid (DHHS Division of Medicaid) | 365 days | Utah Medicaid uses both fee-for-service and managed care. Standard 365-day window. Verify with Utah Medicaid MMIS. |
| Vermont | Green Mountain Care / Vermont Medicaid (DVHA) | 365 days | Vermont Medicaid primarily fee-for-service. Standard 365-day window. |
| Virginia | Virginia Medicaid (Medallion 4.0 / CCC Plus) | 365 days | Virginia Medicaid managed care through Aetna, Anthem HealthKeepers, Magellan, Molina, Optima, and UHC. All follow the 365-day state standard. |
| Washington | Apple Health (Washington State Medicaid / HCA) | 365 days | Washington Apple Health managed care through Coordinated Care, Community Health Plan of Washington, Molina, and UHC. All follow 365-day state standard. |
| West Virginia | WV Medicaid (Mountain Health Trust / BMS) | 365 days | WV Medicaid managed through Aetna Better Health, MSOC Health (WV only), and WellCare by Centene. All follow the 365-day state standard. |
| Wisconsin | ForwardHealth / BadgerCare Plus (DHS) | 365 days | Wisconsin ForwardHealth managed care and fee-for-service both follow the 365-day standard. ForwardHealth portal claims required. |
| Wyoming | Wyoming Medicaid (DHHS) | 365 days | Wyoming primarily fee-for-service. Standard 365-day window. One of the smallest Medicaid populations nationally. |
If your practice bills New York Medicaid or Texas TMHP, timely filing must be a top-of-queue priority in your billing workflow. A 90-day window leaves almost no buffer for claims that require eligibility verification, prior authorization confirmation, or corrected charge capture after the date of service.
Free Tool: Claim Filing Deadline Checker (Above)
Select any payer — including all 51 state Medicaid programs — enter your DOS, and get an exact deadline, live countdown, and safe-submit-by date. Export directly to Outlook or Google Calendar. Use the tool now ↑ — or try the Batch Queue tab to process an entire claim worklist at once.
Secondary Claim Timely Filing Rules
Secondary claims are among the most frequently denied for timely filing — not because practices forget to submit them, but because they use the wrong start date for the filing clock.
For secondary claims, the timely filing window is almost universally measured from the primary payer's Explanation of Benefits (EOB) date, not the original date of service. This is a critical distinction:
| Scenario | Clock Starts From | Typical Window |
|---|---|---|
| Standard secondary claim (commercial) | Primary payer EOB date | 90–180 days |
| Medicare as secondary (MSP) | Date of service or primary EOB | Up to 3 years (MSP rules) |
| Medicaid as secondary (crossover) | Primary EOB date | Varies by state |
| Workers' Comp coordination | Final determination date | 90 days (varies by state) |
The safest billing practice for secondary claims: enter the actual primary EOB date into your practice management system the day you receive it, and immediately trigger the secondary claim workflow. Do not wait until the secondary deadline is approaching — by then, the window may already have closed.
✅ Best Practice
The Claim Filing Deadline Checker above includes a dedicated Primary EOB Date field for secondary claims. Entering the actual EOB date — instead of the DOS — calculates an accurate secondary deadline from the correct start point. Always use the EOB date for secondary claim deadline math.
Timely Filing Rules by Claim Type
The timely filing clock does not work the same way for every claim type. Corrected claims, secondary claims, appeals, and coordination of benefits submissions each have their own start date, window, and documentation requirements. Using the wrong start date is one of the most common causes of avoidable CO-29 denials.
| Claim Type | CMS Frequency Code | Typical Filing Window | Clock Starts From | Key Rules & Caveats |
|---|---|---|---|---|
| Original Claim | Freq. 1 (professional) / Admit-through-discharge (institutional) | Payer-specific (see table above) | Date of service (DOS) | The primary submission. All timely filing clocks start here unless an exception applies (retro eligibility, secondary payer, etc.). |
| Corrected / Amended Claim | Freq. 7 (institutional) / "Corrected" box on CMS-1500 | Same as original claim window | Original DOS — not the correction date | Most payers treat corrected claims as if filed on the original submission date — but only if the original was submitted timely. A corrected claim submitted after the deadline does not reset the clock. Always include the original claim number (ICN/DCN) on the corrected claim. |
| Replacement Claim | Freq. 6 (institutional) | Same as original claim window | Original DOS | A replacement claim voids the original and replaces it in full. Used when the original claim had multiple billing errors. The filing window is the same as the original — the replacement must be within the timely filing window. |
| Void / Cancel of Prior Claim | Freq. 8 (institutional) | N/A — administrative action | N/A | A void cancels the original claim entirely. No separate filing window applies — but the subsequent replacement claim (Freq. 6) must be within the original timely filing window. |
| Late Charge | Freq. 5 (institutional) | Payer-specific (commonly 365 days) | Date of the original claim payment | Late charges for additional services billed after the original claim was paid. Medicare allows late charge bills within 365 days of the original claim payment date. Commercial payers vary — verify your provider manual. |
| Secondary Claim (COB) | Same as original type (professional or institutional) | 90–180 days (commercial) / Up to 3 years (Medicare MSP) | Primary payer's EOB date — not the DOS | The most commonly miscalculated deadline. The secondary timely filing clock starts when the primary EOB is issued — not when the service occurred. For Medicare as Secondary Payer (MSP), providers have up to 3 years from DOS or primary EOB under 42 CFR §489.20. Always enter the EOB date, not the DOS, in the Claim Filing Deadline Checker above. |
| Tertiary Claim | Same as original type | Varies — typically 90–180 days | Secondary payer's EOB date | Third-level coordination of benefits, filed after the secondary payer has processed. Clock starts from the secondary EOB. Common in dual-eligible Medicare/Medicaid patients and coordination with supplemental plans (Medigap). Include both primary and secondary EOBs with the tertiary claim. |
| Crossover Claim (Medicare → Medicaid) | Institutional or professional | Typically auto-crossover within 90 days | Medicare payment date | For dual-eligible patients, Medicare claims typically cross over to Medicaid automatically via the Coordination of Benefits Contractor (COBC). If a claim does not cross over automatically, providers may need to submit manually — verify with your state Medicaid fiscal agent. Manual crossover submissions follow state Medicaid filing windows. |
| Appeal / Reconsideration (Medicare) | N/A — administrative action, not a new claim | 120 days from denial notice | Date of denial notice (Remittance Advice / EOB) | Medicare allows 120 days from the denial notice for a Redetermination (Level 1 appeal). Subsequent levels: Reconsideration (180 days), ALJ Hearing (60 days), DAB/MAC Council (60 days), Federal Court (60 days). CO-29 appeals must include documented proof of timely submission — a favorable appeal decision is not guaranteed without this evidence. |
| Commercial Appeal / Grievance | N/A — payer-specific process | 60–180 days from denial | Date of Explanation of Benefits (EOB) / denial letter | Commercial payer appeal windows vary by contract. Most allow 60–180 days from the denial date. ERISA self-funded plans may have as little as 60 days. For CO-29 appeals specifically, attach the clearinghouse 277CA acknowledgment, EHR audit log, or certified mail receipt. Always request a written appeal decision and track the internal appeal reference number. |
| State Medicaid Appeal | N/A — state-specific process | 30–120 days from denial | Date of denial / Remittance Advice | State Medicaid appeal windows vary significantly. New York: 60 days. Texas (TMHP): 120 days. Most states: 30–90 days. Missing the appeal window on a Medicaid CO-29 denial is generally permanent. File appeals immediately upon receipt of denial RA. |
| Newborn / Delivery Claim | Professional or institutional | Payer-specific (commonly 90–365 days) | Date of delivery (mother's DOS) or newborn's DOS | Newborn claims are frequently delayed due to eligibility processing. Most payers restart the timely filing clock from the date newborn eligibility is confirmed — especially important for Medicaid newborns whose enrollment may not process until 30–60 days after birth. Document the Medicaid confirmation date and use it as the start date if eligibility was retroactively assigned. |
| Split Billing / Part B Inpatient | Freq. 1 (professional) on inpatient DOS | Payer-specific from DOS | Individual DOS of each service | When a Part A inpatient claim is denied and the physician re-bills under Part B (split billing), the timely filing window is measured from each individual DOS — not the discharge date. This is critical for services spanning multiple days. |
| Coordination of Benefits — Workers' Comp Primary | Professional or institutional | 30–90 days from WC determination | Date of Workers' Comp final determination or denial | When Workers' Compensation is primary and denies the claim (or reaches a final determination), the health insurer becomes primary. The timely filing clock for the health plan typically starts from the WC determination date — but may be subject to state-specific rules. File the health plan claim within 30 days of the WC outcome to be safe. |
| Home Health / Hospice (OASIS-based) | Institutional (UB-04) / RAP and Final | 365 days (Medicare) | Episode start date (RAP) / Episode end date (Final claim) | Medicare Home Health and Hospice claims follow the standard Medicare 365-day timely filing rule per 42 CFR §424.44. RAP submissions must be within 5 days of episode start under PDGM. Final claims must follow within 60 days of episode end or the RAP is cancelled. |
| Durable Medical Equipment (DME) | Professional (CMS-1500) / DMEPOS | 365 days (Medicare) / varies commercial | Date of delivery or first use | Medicare DME follows 365-day timely filing from the date of delivery. Rental equipment: clock starts each month from the monthly delivery date. Prior Authorization required for most DME items over $1,000 — missing PA = CO-97, not CO-29. Verify PA status with the PA Check tool before billing. |
| Mental Health / Behavioral Health | Professional (CMS-1500) | 90–180 days (varies by payer) | Date of service | Many behavioral health claims are carved out to a separate payer (Magellan, Beacon, Optum Behavioral). Always verify the behavioral health carve-out payer and its specific timely filing deadline — it may differ from the medical plan. Carve-out payers frequently have 90–120 day windows even when the medical plan allows 180 days. |
| Pharmacy / Part D | NCPDP (pharmacy-specific) | Varies — typically 30–365 days | Date of dispensing | Pharmacy claims use NCPDP billing formats, not ANSI X12. Timely filing windows vary by PBM (Caremark, ExpressScripts, OptumRx). Most PBMs: 90–365 days from date of dispensing. Long-term care pharmacy: 365 days for most Part D plans. Verify with the specific PBM. |
💡 A Note on Frequency Codes
CMS claim frequency type codes (1 through 8) are used on institutional (UB-04) claims to indicate whether a claim is original, corrected, replacement, or void. Professional claims (CMS-1500) do not use frequency codes in the same way — corrections are submitted with a reference to the original ICN/DCN and a notation that the claim is corrected. Always confirm the correct claim frequency and replacement methodology with your clearinghouse or billing software documentation.
Retroactive Eligibility & Timely Filing Exceptions
Retroactive eligibility is one of the most commonly mishandled exceptions in medical billing. It occurs when a patient's insurance coverage is approved or confirmed after the date of service — often because of:
- Late Medicaid enrollment processing by the state agency
- Employer group plan enrollment delays
- Appeals of prior insurance terminations that result in retroactive reinstatement
- Newborn coverage that retroactively covers the birth date
In retroactive eligibility situations, the timely filing clock typically restarts from the date eligibility was confirmed or made known to the provider — not the original DOS. CMS explicitly recognizes this for Medicare under its good-cause exception framework. Most commercial payers follow similar logic, though the language varies by contract.
When a provider could not have known about a patient's eligibility at the time of service, penalizing them for filing after a deadline that effectively didn't exist yet contradicts both contract intent and payer fairness standards.
— CMS Provider Relations Policy Guidance, Retroactive Eligibility
What to Do When You Discover Retroactive Eligibility
- Document the exact date you received the eligibility confirmation — from the payer portal, ERA, or eligibility verification system.
- Use that confirmation date as the timely filing start date (not the DOS).
- Submit the claim with a cover note referencing retroactive eligibility and the confirmation date.
- If denied, appeal with the eligibility confirmation documentation and cite the payer's good-cause exception provision.
The Audit Guard tool at CureAdvantage can help you identify retroactive eligibility claims in your aging AR before their appeal windows close.
Is Your Practice Losing Revenue to CO-29 Denials?
Our RCM specialists audit your denial patterns, identify recurring timely filing issues, and build workflows that recover revenue before deadlines expire.
How to Appeal a CO-29 Denial
A CO-29 denial is not automatically final. Most payers maintain a formal appeal process for timely filing denials where proof of prior timely submission can overturn the denial. The appeal window itself is typically:
- Medicare: 120 days from the date of the denial notice (Redetermination level)
- Commercial payers: 60–180 days from the denial date (varies by payer contract)
- Medicaid: Varies by state, typically 30–120 days from denial
What Documentation Do You Need for a CO-29 Appeal?
The strength of a CO-29 appeal depends entirely on the quality of your submission evidence. Acceptable proof of timely submission includes:
| Evidence Type | Strength | Details |
|---|---|---|
| Clearinghouse 277CA acknowledgment | 🟢 Strongest | Electronic confirmation from your clearinghouse with submission timestamp and payer-accepted status. This is the gold standard. |
| EHR / PMS submission audit log | 🟢 Strong | System-generated timestamp showing when the claim was transmitted. Must be uneditable and include the claim ID. |
| 835 ERA with original receipt date | 🟡 Moderate | Electronic remittance showing the original claim receipt date from the payer's system. |
| Certified mail receipt | 🟡 Moderate | USPS tracking with delivery timestamp before the deadline. Only applicable for paper submissions. |
| Fax confirmation report | 🟡 Moderate | Dated fax transmission report to the correct payer fax number. Weaker than electronic confirmation. |
| Internal billing notes only | 🔴 Weak | Not accepted by most payers without corroborating external evidence. |
CO-29 Appeal Letter: Key Components
Your CO-29 appeal letter should include:
- Patient name, DOB, member ID, claim number, and DOS
- The denial date and the CARC code (CO-29)
- A clear statement that the claim was submitted timely — with the exact original submission date
- All attached documentation (clearinghouse report, audit log, etc.)
- A request for review under the payer's timely filing appeal provision
- If applicable: a good-cause exception argument (payer system error, retroactive eligibility, natural disaster, etc.)
✅ Always Keep Your Clearinghouse Reports
The 277CA claim acknowledgment from your clearinghouse is your single most powerful protection against CO-29 appeals. Configure your billing system to archive all 277CA reports for a minimum of 7 years — consistent with HIPAA record retention standards and most state medical record laws. Use the Audit Guard tool to flag claims missing acknowledgment records.
8-Step Workflow to Prevent Timely Filing Denials
CO-29 denials are almost 100% preventable with the right internal controls. The following workflow is designed for practices billing multiple payers with different filing windows — the scenario that most commonly produces timely filing misses.
1
Document Every Payer's Filing Window at Contracting
When you sign or renew any provider contract, extract the timely filing limit and enter it into your practice management system as a payer-level setting. Flag any payer with a window under 180 days for elevated priority handling.
2
Verify Insurance Eligibility at Every Visit — Not Just New Patients
Eligibility verification at the point of care is your first defense. Use the PA Check tool to confirm active coverage and benefit limits before services are rendered. Catching eligibility gaps early prevents the retroactive eligibility scrambles that trigger filing deadline crises.
3
Submit Claims Within 7 Days of the Date of Service
A 7-day internal submission target gives you the maximum possible buffer for corrections, rejections, and resubmissions — while keeping all payers well inside their filing windows. Practices that target next-day submission achieve significantly higher first-pass acceptance rates.
4
Archive Every Clearinghouse Acknowledgment
Configure your clearinghouse to deliver and retain 277CA acknowledgment files for every submitted claim. If your current clearinghouse doesn't provide 277CA reports, this is a legitimate reason to switch. No acknowledgment = no CO-29 appeal defense.
5
Run a Weekly Aging AR Report Filtered by Days to Deadline
Every week, pull an AR aging report sorted by filing deadline — not by dollar amount. Claims approaching their deadline deserve priority regardless of balance. Use the Revenue Leakage Calculator to quantify what timely filing misses are actually costing your practice.
6
Build Calendar Alerts for At-Risk Claims
For any claim not yet resolved within 30 days of its filing deadline, set a calendar alert at 30, 14, and 7 days before expiration. The Claim Filing Deadline Checker above generates .ics calendar files with embedded alerts — one per claim — that import directly into Outlook and Google Calendar.
7
Flag Secondary Claims for Immediate Action Upon Receipt of Primary EOB
The day a primary EOB arrives — whether by ERA or paper — your secondary claim workflow should begin. Don't let EOBs sit in a queue. The secondary filing clock starts the day the EOB is dated, not the day you open it.
8
Conduct a Monthly CO-29 Root Cause Review
Any CO-29 denial that reaches your desk is a process failure, not just a billing error. Monthly, review every CO-29 to identify where in the workflow the claim fell through — whether that's charge capture delay, payer eligibility confusion, or missing clearinghouse connectivity. Use the Audit Guard tool to run a structured billing audit and identify systemic gaps before they produce more CO-29s.
Frequently Asked Questions
What is a timely filing limit in medical billing?
A timely filing limit is the maximum number of days a provider has to submit a health insurance claim after the date of service. Deadlines range from 90 days (New York Medicaid, UnitedHealthcare in-network) to 365 days (Medicare Part A & B, TRICARE). Missing this deadline results in a CO-29 denial and permanent loss of reimbursement unless a valid appeal with proof of timely submission is filed.
What is a CO-29 denial code in medical billing?
CO-29 is a Claim Adjustment Reason Code (CARC) meaning the claim was denied because it was submitted after the payer's timely filing deadline. CO-29 denials are generally not payable unless the provider can prove the claim was originally submitted on time — through a clearinghouse 277CA confirmation, EHR audit log, or certified mail receipt timestamped before the deadline.
How do you appeal a CO-29 denial?
To appeal a CO-29 denial, gather documented proof that the original claim was submitted before the deadline — a clearinghouse 277CA acknowledgment with timestamp, EHR submission log, or certified mail receipt. Submit a formal appeal letter citing the CO-29 denial date, attach all evidence, and request a good-cause exception if applicable (payer system errors, natural disasters, retroactive eligibility). Medicare allows 120 days from the denial notice at the Redetermination level. Most commercial payers allow 60–180 days from the denial date.
What is Medicare's timely filing limit?
Medicare Part A and Part B require all claims to be filed within 365 days (12 months) of the date of service, per 42 CFR §424.44. This applies to original claims, corrected claims, and late charge bills. Note: Medicare Advantage (Part C) plans are administered by private insurers and are not bound by this 365-day rule — always verify your specific Medicare Advantage plan's filing window separately.
What is the timely filing limit for secondary claims?
For secondary claims, the timely filing clock typically starts from the primary payer's EOB date — not the date of service. Most commercial payers allow 90 to 180 days from the primary EOB date. Medicare secondary claims have up to 3 years under Medicare Secondary Payer (MSP) rules. Always enter the actual EOB date (not the DOS) when calculating secondary claim deadlines. The Claim Filing Deadline Checker above has a dedicated EOB Date field for accurate secondary deadline calculation.
How does retroactive eligibility affect timely filing?
When a patient's insurance eligibility is confirmed retroactively after the date of service, most payers — including Medicare and many commercial payers — restart the timely filing clock from the eligibility confirmation date, not the original DOS. Providers should document the exact date the retro eligibility was confirmed and use that date as the filing start date. If denied despite this, cite the payer's good-cause exception provision and attach the eligibility confirmation documentation in the appeal.
Which state Medicaid programs have the shortest timely filing limits?
As of 2026, the states with the shortest Medicaid timely filing windows are: New York (90 days via eMedNY), Texas (95 days via TMHP), Illinois (180 days), Indiana (180 days via Healthy Indiana Plan), and New Jersey (180 days via NJ FamilyCare). All other states use a standard 365-day window. Providers billing in New York or Texas must treat Medicaid claims as high-priority from the moment of service.
Can you bill the patient when a CO-29 denial is issued?
In almost all cases, no. Under most provider agreements, timely filing denials are classified as an administrative failure on the provider's part. Shifting this write-off to the patient is generally prohibited by your payer contract and may also violate state balance billing laws. Before writing off a CO-29 balance, always exhaust your appeal rights and check whether your contract includes any explicit exception that permits balance billing for timely filing denials.
📚 Sources & References
- 42 CFR §424.44 — Timely Filing Requirements for Medicare Claims, Electronic Code of Federal Regulations (eCFR)
- CMS Medicare Timely Filing Policy, Centers for Medicare & Medicaid Services
- CARC CO-29 Code Descriptor, AAPC Claim Adjustment Reason Code Reference
- Healthcare Financial Management Association (HFMA) — Denials Management Research, 2024
- American Medical Association (AMA) — 2023 Prior Authorization Survey & Denial Data
- X12 CARC/RARC Code Committee — Official Claim Adjustment Reason Code Definitions (current release)
- State Medicaid Agency Provider Manuals: eMedNY (NY), TMHP (TX), Illinois HFS, Indiana OMPP, NJ DMAHS — accessed June 2026
- Eman Zahra, "How AI Is Transforming Medical Billing Practices in 2026," CureAdvantage (May 2026)