Common denial reasons
Fastora’s denial management services give your practice a team that works every denied claim to a clear outcome instead of letting it sit. Our medical billing denial management covers the full loop: reading the payer’s reason, correcting or appealing the claim, and changing the upstream step that caused it. This is healthcare denial management built for physician practices and outpatient providers, handled by certified medical billing and coding professionals.
Payers report denials with Claim Adjustment Reason Codes (CARCs) and Remittance Advice Remark Codes (RARCs) on the remittance. These codes tell you what the payer objected to, but not always why it happened in your office. Most denial reasons trace back to a short list of causes:
- Eligibility and coverage: the plan was inactive, a different payer administers the benefit, or another plan should have paid first.
- Authorization: a required approval was missing, expired, or did not cover the visits or units billed.
- Coding and modifiers: diagnosis codes that do not support the service, missing modifiers, or bundling edits.
- Documentation and medical necessity: the record does not show what the payer’s coverage policy requires.
- Duplicates and timely filing: corrections sent as new claims, or claims filed after the payer’s deadline.
- Provider enrollment: the rendering provider is not yet credentialed or linked to the group with that payer.
Eligibility denials
Coverage denials such as CO-27 (expenses incurred after coverage ended) usually start at registration: an old card on file, a plan change at the new year, or a secondary plan billed as primary. The fix is a corrected claim to the right payer, and the prevention is a fresh eligibility check before each visit.
Authorization denials (CO-197)
CO-197 means the payer found no precertification, authorization or notification for the service. Before appealing, we check whether an approval exists under a different provider, date range or code, because a data mismatch can often be corrected. If no approval was obtained, a retro authorization request or appeal is only an option where the payer’s policy allows it.
Medical necessity (CO-50)
CO-50 means the payer did not consider the service medically necessary under its coverage policy. These denials are worked by comparing the chart note and diagnosis codes with the payer’s published policy, then appealing with the records that meet each criterion, or confirming whether the patient signed a waiver or advance notice before the service.
Timely filing (CO-29)
CO-29 means the payer’s time limit for filing has expired. The only reliable answer is proof: a clearinghouse acceptance report or payer acknowledgment showing the claim arrived on time. Without that proof, the balance is usually an adjustment, and many network contracts bar billing the patient for it. Our guide to reading CARC and RARC codes covers more of these codes.
How we work denials: the claim denial management process
Claims denial management works best as a daily routine, not a quarterly cleanup. Denials are pulled from ERAs and payer correspondence as payments post, so no denied claim waits for someone to notice it.
- Capture: every denial and rejection is logged with payer, reason code, date of service and amount.
- Triage: items are sorted by deadline and value, so claims closest to a payer’s appeal or corrected-claim window are worked first.
- Research: the biller reviews the claim, the chart note and the payer’s policy to decide whether the claim needs a correction, an appeal or an adjustment recommendation.
- Denial resolution: the claim is corrected and resubmitted, appealed with supporting records, or routed to your office when a provider signature or addendum is needed.
- Follow-up: every resubmission and appeal is tracked until the payer issues a final decision.
Denied claims management also means knowing when to stop. If a service is not covered and the patient agreed in writing to pay for it, the balance may move to patient billing rather than into another appeal.
Denial prevention at the front end
Denial prevention starts before the patient arrives. In Fastora’s Virtual Assistant phase, our team verifies insurance, confirms authorization requirements and collects co-pays upfront, which removes several of the most common front-end causes of denials. See how checking coverage before the visit feeds this step.
Before a claim goes out, Advanced Pre-Submission Claim Review checks it against payer requirements: patient and policy details, code pairs, modifiers, place of service and rendering provider. An error caught at this stage can be fixed the same day, while the same error found after adjudication turns into a denial that has to be researched and resubmitted.
Appeals we write: corrected claims, reconsiderations and appeal levels
Not every denial needs an appeal. Choosing the right route saves time and keeps the claim history clean with the payer.
| Route | When it fits | What it involves |
|---|---|---|
| Corrected claim | The original claim had a data error, such as a wrong code, modifier, date or member ID | A replacement claim (claim frequency code 7) that references the original claim number |
| Appeal | The payer processed the claim as billed, but the decision is wrong, such as a medical necessity or bundling denial | A written request with the relevant records and payer policy, filed within the payer’s appeal window |
| Reopening (Medicare) | A minor clerical error on a Medicare claim | A reopening request to the Medicare contractor instead of a formal appeal |
Our medical claim appeals services include drafting the appeal letter, attaching the records that answer the payer’s specific objection, and tracking each level of review. Medical billing appeals can move through several levels: Medicare has five, starting with a redetermination by the Medicare contractor, which generally must be requested within 120 days of receiving the initial determination. Commercial plans set their own reconsideration, internal appeal and external review steps, so we record each payer’s windows from its provider manual and your contract.
Appeals are strongest when they respond directly to the reason code on the denial. A letter that simply asks the payer to reconsider rarely changes the outcome. Our claim appeals services also track first-pass resolution: how many denials are settled by the first corrected claim or appeal, without a second round. If a payer has already taken money back, our payer clawback and recoupment guide explains your options.
Root-cause prevention: root cause denial analysis
Working denials one by one brings in revenue, but denial recovery alone leaves the cause in place. Root cause denial analysis groups denials by reason, payer, provider, location and service to show where the process broke. Typical findings look like this:
- A cluster of eligibility denials from one location points to a registration step being skipped.
- Repeated modifier denials on one service suggest a charge template needs updating.
- Authorization denials that begin after a certain visit often mean visit counts are not tracked against the approval.
- Enrollment denials for a new provider signal that billing started before payer approval was complete.
Each finding is paired with a specific fix and an owner, whether that is our team, your front desk or a documentation change for a provider. Our article on practical ways to prevent denials covers more of these fixes.
Medical billing denial management by specialty
Denial patterns differ by specialty, so our review checklist changes with the practice.
Behavioral health
Behavioral health claim denials often come from plans that carve out mental health benefits to a separate administrator, session time that does not support the psychotherapy code billed, missing authorization for higher levels of care, and provider license types a plan does not cover. Our behavioral health billing team checks these points before and after submission.
Physical therapy
Physical therapy claim denials tend to involve visit limits, expired authorizations, missing plan of care certification for Medicare patients, and timed units that do not match documented minutes. Medicare also requires the KX modifier on therapy claims above an annual threshold to confirm medical necessity. Our physical therapy billing workflows track each of these.
Outsourced denial management alongside your team
Outsourced denial management works best when roles are clear. Fastora’s team captures, researches and resubmits denials, while your office supplies what only the practice can: a provider addendum, a signed record, or a decision on a patient balance. A dedicated account contact routes those requests, so nothing waits in a shared inbox.
Denial management in medical billing is also tied to follow-up on everything else in your A/R. Denials found during claim status checks feed the same queue, and our A/R follow-up service keeps unpaid claims moving while denials are worked. If a previous vendor left a large set of unworked denials, a separate old A/R recovery project can size that backlog and work it against payer deadlines.
When you compare a denial management company, ask how it decides between a corrected claim and an appeal, how it tracks appeal deadlines by payer, and whether its reports show root causes or only totals. Fastora works inside your existing EHR/PM system with no software to install and signs a Business Associate Agreement before accessing PHI.
Denial reporting with our denial management services
Denial reporting is part of Fastora’s monthly performance reporting, with a review call to walk through it. Transparent dashboards let you check progress between calls, and custom reports are available on request. Each month covers:
- Denials by reason, payer and provider, compared with prior months
- Open denials by age, with the next action on each
- Appeal outcomes by payer
- Root causes found and the fixes in progress
If you want a baseline first, Fastora offers a free claims audit that works as a denial analysis: it reviews your current denial patterns by reason and payer before you commit to anything. See where you stand with our denial rate calculator.
What does insurance denial management include?
Insurance denial management covers the full loop on every denied claim: reading the payer reason codes, correcting or appealing the claim through the right route, and fixing the upstream cause — eligibility, authorization, coding or workflow — so the denial does not repeat. It also covers the patterns: denials grouped by reason, payer and provider each month, which is where prevention starts. Our A/R management service works the aging that denials leave behind. Our article on the claim status follow-up workflow walks through the daily routine. When a payer takes money back after paying, that is a different fight — see our payer clawback and recoupment guide.
Denial prevention services and strategies
Our denial prevention services start with the medical billing denial reasons your practice actually sees: eligibility lapses, missing authorizations, coding errors, and timely filing misses. Denial prevention strategies then target the top few — front-end checks for eligibility and authorization, coding denial prevention through pre-submission review, and claim edits tuned to the payers that deny you most. Prevention is measured monthly: denials grouped by reason, payer, and provider, so the same cause does not repeat.
Denial appeals services and denial recovery
When prevention misses a claim, denial appeals services take over: corrected claims, redeterminations, and formal appeals with medical records and payer-specific forms. Insurance appeals services cover the same path when the authorization — not the claim — was denied. Denial recovery services go further back, reopening aged denials still inside timely filing and payer reconsideration windows. This is medical claim denial management end to end: every denial categorized, worked, and tracked to a decision. Our article on how to appeal a denied claim walks through the steps.
CO-18 and CO-29 denial codes
Two CARC codes show up constantly. The CO-18 denial code means a duplicate claim or service — usually a resubmission that crossed with an original still in process, fixed by checking claim status before resending. The CO-29 denial code means the time limit for filing has expired: timely filing lapsed, and the fix is prevention — claims out the door on a daily rhythm — since few payers reopen a truly late claim. One more distinction that changes the fix: the difference between rejection and denial. A rejection never reached adjudication — the clearinghouse or payer front end bounced it, so you fix and resend. A denial was adjudicated and decided against you, so it needs correction or appeal. See our CARC denial code guide for the full code list.
Underpayment recovery: contract underpayment analysis
Payer underpayment recovery starts with contract underpayment analysis — comparing what was actually paid against the contracted rate, line by line. Medical billing underpayment recovery covers both contract shortfalls and claims paid at the wrong fee-schedule version, and the recovered amounts are reported separately from collections so you can see them. A denial management company that also audits contracts catches the underpayments that never appear as denials. What is denial management in medical billing, in practice? Tracking every denied and underpaid claim to a resolution — correction, appeal, or a write-off you approved — and fixing the upstream cause so the pattern stops. Our A/R management service works the aging denials leave behind and our underpayment recovery service handles the contract side.
