Denial management in depth: causes, benchmarks and appeal rules
Denial management is the process of finding out why a payer refused a claim, correcting or appealing it, and fixing the cause so it does not happen again. A denial is different from a rejection: a rejection is stopped by the clearinghouse or payer front end before adjudication, while a denial is a payer decision with a reason code.
Why claims are denied
Every denial carries a Claim Adjustment Reason Code (CARC), often with a Remittance Advice Remark Code (RARC). These are the codes billing teams see most often.
| CARC | What it means | Typical prevention |
|---|---|---|
| 16 | Claim lacks information or has a billing error | Claim scrubbing and required-field checks |
| 18 | Duplicate claim or service | Check claim status before resubmitting |
| 27 | Service after coverage ended | Eligibility verification before the visit |
| 29 | Timely filing limit expired | Track filing deadlines by payer |
| 50 | Not deemed medically necessary | Documentation that meets payer or Medicare LCD/NCD policy |
| 97 | Service included in payment for another service | NCCI edits and correct modifiers |
| 197 | Authorization or precertification absent | Prior authorization tracking |
Denial rate benchmarks
Denial rate is denied claims divided by claims submitted. An initial denial rate under 5 percent is a commonly cited best-practice target, though specialty and payer mix change what is realistic. Track the rate by payer, CPT code and provider, and separate preventable denials (registration, authorization, coding) from clinical or contractual ones.
Appeal deadlines and timely filing
Deadlines decide whether a denial can still be recovered. Medicare’s timely filing limit is one calendar year from the date of service, and a Medicare Part B redetermination must be requested within 120 days of the initial determination. Commercial and Medicaid deadlines are set by contract or state rules, so the window printed on the denial notice or remittance is the one that applies.
Payer and regulatory rules
Medicare Advantage plans, state Medicaid managed care plans and commercial payers such as Anthem Blue Cross Blue Shield, UnitedHealthcare, Aetna and Cigna each publish their own medical policies, prior authorization lists and appeal procedures. Effective denial work follows the payer’s current policy, the CMS National Correct Coding Initiative edits and the relevant Local or National Coverage Determination.
What a denial management workflow includes
- Sort every denial by CARC and RARC, payer, CPT code and provider.
- Decide whether the claim needs a correction and resubmission or a formal appeal, and confirm the deadline.
- Prepare the appeal with records, authorization proof and a clear medical necessity or coding rationale.
- Track each appeal to a final decision and escalate when a payer misapplies its own policy.
- Report root causes monthly and fix them upstream in eligibility, authorization, charge entry or coding.
Metrics to review each month
- Initial denial rate and top five denial reasons by payer
- Appeal volume and overturn rate
- Days in A/R and net collection rate
- Dollars at risk by age and filing deadline