The 10 Most Common Reasons Health Insurance Claims Are Denied

The 10 Most Common Health Insurance Claim Denial Reasons

1. Not medically necessary — The insurer's reviewer determines the treatment was elective or not clinically required. This is the single most common denial reason and is frequently successfully appealed with physician-authored clinical documentation.
2. Pre-existing condition exclusion — The insurer argues the condition existed before the policy start date. Often misapplied — particularly when the current condition is distinct from any prior diagnosis.
3. Out-of-network provider — Treatment received from a facility or physician not on the insurer's approved list. Emergency exceptions apply in most markets.
4. Missing pre-authorisation — Certain procedures required advance approval that was not obtained. Retrospective authorisation may be available where clinical urgency can be demonstrated.
5. Incomplete or incorrect documentation — Missing clinical notes, referral letters, or itemised invoices. Often the easiest denial type to reverse.
6. Plan exclusion applied — The treatment falls under a listed exclusion. Check whether the exclusion actually applies to the specific procedure or diagnosis code billed.
7. Benefit limit reached — The claim exceeds the annual or per-condition benefit limit. Review whether the correct limit was applied and whether benefits accumulated correctly.
8. Policy lapsed or not active — Coverage was not active on the date of service. Check employer payroll records if this applies to a group plan.
9. Coordination of benefits issue — Where you have two policies, the insurer argues the other policy should pay first. Verify which is primary and which is secondary under your specific plans.
10. Incorrect billing code — The facility billed with a code that maps to an excluded service. Ask the provider to review the billing and resubmit with the correct code.

Every one of these denial reasons can be challenged. The key is knowing which argument applies to your specific situation. HealthPlan Advise reviews your denial and builds the right argument from $10.