Top 9 Claim Denial Reasons & How to Fix Them

The Nine

Top 9 Denial Reasons and the Fix for Each

Each reason, what it costs you, and the process fix that stops it.

Denial reason	What happens	The fix
1. Eligibility / Coverage	Patient not eligible on the date of service, or coverage terminated.	Real-time eligibility on every visit, not just new patients. Self-pay protocol when coverage cannot be confirmed.
2. Prior Authorization	Service required auth that was never obtained or not on the claim.	Capture the auth number at scheduling and verify it before the visit. Track auth balances like a bank account.
3. Medical Necessity	Payer says the diagnosis does not support the service.	Check LCD/NCD coverage before billing. Strengthen documentation with medical-necessity language.
4. Timely Filing	Claim arrived after the payer deadline. Almost never overturned.	Submit within 24 hours of the encounter. Sort AR queues by filing deadline, not by age.
5. Coding Errors	Wrong CPT or ICD-10, bundling violations, missing modifiers.	Pre-bill scrubbing against NCCI edits, MUE limits and payer rules on every claim.
6. Invalid / Missing Info	Demographics, NPI, or dates do not match payer records.	Demographic QA at registration plus a claim scrubber that validates NPI, taxonomy and POS.
7. Duplicate Claims	Payer believes it already processed the claim.	Check claim status before any resubmission. Use frequency codes 7 and 8 for corrected claims.
8. Non-Covered Services	Service excluded from the patient's benefit plan.	Verify benefits including exclusions at scheduling. ABN or upfront estimates where appropriate.
9. Coordination of Benefits	Wrong payer order, or COB questionnaire unanswered.	Verify primary/secondary/tertiary at every visit. Capture COB at check-in, not in billing.

The Pattern

What the Top 9 Have in Common

Seven of the nine are preventable before the claim goes out.

Eligibility, auth, coding, info, duplicates and COB denials are all front-end or pre-bill failures - not payer cruelty
Timely filing is pure process loss: every one represents work that sat too long
Medical necessity and non-covered denials are the only two that regularly need clinical judgment
Our denial work starts with prevention rates by cause, then builds the worklist from what is actually recoverable

FAQ

Questions, Answered

Straight answers, no jargon.

What is the most common reason claims are denied?

Eligibility and coverage issues consistently top the list across specialties - the patient was not eligible on the date of service or the wrong payer was billed.

Which denials are hardest to overturn?

Timely filing denials are almost never overturned. Benefit maximums and absolute policy edits (MUE MAI 2) are close behind. Prevention is the only strategy for these.

What is the difference between a rejection and a denial?

A rejection means the claim failed intake edits and never entered adjudication - fix and resubmit. A denial means the payer processed it and refused payment - appeal with a case.

How do you prioritize which denials to work?

By recoverable dollars, not by count. A $2,000 medical-necessity denial with good documentation beats ten $40 duplicates every time.

Can coding denials really be prevented?

Most of them, yes. NCCI pair checks, MUE unit checks, diagnosis-pointer validation and modifier review before submission eliminate the majority of coding denials.

How It Works

From Leaking Revenue to Steady Cash Flow in 4 Steps

The same proven process behind every denial-management engagement.

Free Revenue-Leak Review

Send one billing export. We map denials, AR aging and underpayments - free.

Recovery Plan

You get a prioritized action plan with projected recoveries before you commit.

We Go to Work

Denials appealed, AR worked, workflows fixed - inside your systems.

You Watch It Grow

Transparent reporting. You pay 5% of what we collect - nothing else.

Top 9 Denial Reasons