Top 10 reasons healthcare claims get denied and how to prevent them

Source: ChatGPT
Top 10 reasons healthcare claims get denied and how to prevent them
41% of providers now report that at least one in ten of their claims gets denied, according to Experian Health's 2025 State of Claims survey. That figure has grown every year since 2022.
The frustrating part is that most of those denials are preventable. The same survey found the top three denial reasons have stayed identical year over year. Missing data, authorization failures, and incomplete patient registration keep showing up because the workflows that cause them have not changed.
This guide breaks down the ten most common insurance claim denial reasons and what your team can do to stop them before they hit the queue.
Why fixing denials upstream saves more money than appealing them downstream
Appeals are essential. But a clean claim costs less than a reworked one, every time.
Each denied claim costs between $25 and $181 to rework, depending on complexity. At scale, that adds up fast. Prevention removes the cost before it starts and keeps your billing team focused on revenue instead of rework.
Most denial categories are predictable. Once you know your pattern, you can act on it.
The 10 most common claim denial reasons
1. Missing or inaccurate claim data: This has been the top denial reason for years. In 2025, 50% of revenue cycle leaders cited it as the primary factor behind rising denial rates, up from 46% in 2024, per the Experian Health State of Claims 2025 survey. Pre-submission claim scrubbing tools catch these errors before the claim leaves your system.
2. Prior authorization failures: Payers keep adding services to prior auth lists. 35% of revenue cycle leaders cited authorization issues as a top denial reason in 2025, per Experian Health. Centralizing your prior auth workflows and keeping payer-specific requirement lists current is the most direct fix.
3. Coding errors: Wrong CPT codes, incorrect modifiers, unbundling, and diagnosis mismatches all trigger denials. Coding errors accounted for 25% of audit requests in hospital settings in 2025, per MDaudit data reported by Fierce Healthcare. Regular coder retraining and pre-submission audits are the most effective prevention.
4. Eligibility and coverage issues: Billing the wrong plan, a lapsed policy, or the wrong member ID. These are entirely preventable with real-time eligibility verification at intake. And let's be honest: this one still catches teams off guard more often than it should.
5. Incomplete or missing documentation: The claim goes out but the supporting clinical records do not follow. Payers request additional information, delay payment, or deny outright. Documentation checkpoints built into your intake and charge capture workflow reduce this significantly.
6. Medical necessity denials: The clinical documentation does not adequately support the service billed. Denied inpatient claim amounts rose 12% from 2024 to 2025, per MDaudit. Strong clinical documentation at the point of care is the prevention. Detailed, payer-specific appeal letters are the recovery.
→ For a deeper look at how AI platforms are improving medical necessity appeal outcomes, see this overview of AI platforms for medical necessity appeals.
7. Duplicate claim submissions: The same claim submitted twice, or a corrected claim that payer systems read as a duplicate. This usually comes from manual resubmission without proper tracking. An automated submission system with duplicate detection removes this category almost entirely.
8. Timely filing violations: Every payer has a filing window, usually 90 to 180 days from the date of service. Once it closes, the revenue is gone. Tracking submission deadlines by payer and flagging claims at risk before they expire is a basic step that often gets skipped.
9. Bundling and unbundling errors: Billing separately for services that should be bundled, or the reverse. Payer rules vary and change. A claims editing tool that applies payer-specific bundling logic before submission catches most of these before they become denials.
10. Non-covered services: The service was never covered under the patient's plan, or a coverage exclusion was missed at intake. Verifying coverage details, not just active insurance status, at scheduling prevents this and protects the patient from unexpected bills too.
How to find out which denial reasons are hitting your organization hardest
The general list above helps. Your specific pattern is what drives improvement.
Pull your denial data for the last 90 days and sort by reason code. Which category has the most volume? Which has the most dollar value? Those two questions tend to have different answers, and both matter.
Most billing teams find that two or three denial categories account for the large majority of denied revenue. Addressing those first has far more impact than trying to fix everything at once.
→ This denial prioritization guide covers how to rank and triage your denial queue so your team works the right claims first.
How to build a denial prevention workflow
Denial prevention is a set of checks that run at different points in the claim lifecycle.
At scheduling and intake: Verify eligibility and coverage in real time. Confirm prior authorization requirements for the service being scheduled. Collect complete demographic information while the patient is in front of you.
At documentation: Make sure clinical notes support the service being billed. Flag services with high medical necessity denial rates and give clinicians a prompt to document more specifically.
At charge capture: Review CPT and diagnosis codes before the claim is built. Apply payer-specific bundling rules. Check for common modifier errors.
At pre-submission: Run a claim scrub that checks for missing data, code accuracy, eligibility, and prior auth. Fixing errors here costs nothing. Fixing them after a denial costs time and money.
At submission: Use the payer's preferred channel. Track every claim against its expected response window and flag anything overdue before the deadline passes.
Can prevention reduce denial rates over time?
Yes, consistently. The Experian Health State of Claims 2025 survey found that among providers already using AI-driven tools in the claims process, 69% reported a reduction in denials or an improvement in resubmission success rates. The catch: only 14% of providers are currently using AI for this purpose.
That gap between what works and what teams have actually put in place is where a lot of recoverable revenue is waiting.
Where most denial prevention programs fall short
Many teams know what the problems are. But most of them do not have the systems to catch them consistently.
The most common gap is at intake. 26% of providers say at least one in ten of their denials traces back to incomplete or inaccurate data collected at registration. That is before a single claim is ever built.
The second gap is prior auth tracking. Requirements change by payer, by service type, and sometimes by plan year. Teams relying on static reference lists will miss updates. And missing one authorization is enough to lose the claim.
The third gap is pre-submission review. Many practices still run manual scrubs, or skip them when the queue is full. That is where preventable coding errors and missing modifiers slip through.
Healthcare claims denial management platforms address all three gaps through automation. They pull live eligibility data, flag prior auth requirements against current payer rules, and run claim-level scrubs before submission, without adding steps for your team.
What happens when you combine prevention with a structured appeals process?
Prevention reduces how many claims come back denied. A structured appeals process recovers the ones that still do.
Organizations that work on both at the same time tend to see the biggest improvement in their overall denial rate and their recovery rate.
If you're dealing with revenue gaps from a backlog of past denials alongside a prevention project, this breakdown of healthcare revenue recovery solutions covers how to work both problems in parallel.
And if you want to see how the full workflow fits together from insurance claim denial prevention through to resolution, this guide to healthcare claims denial management explains it end to end.
How automation supports denial prevention at scale
Manual prevention workflows work at low volume. At higher volumes, steps get skipped and errors slip through.
Automated platforms run the same checks on every claim, every time: eligibility verification, prior auth tracking, code audits, and pre-submission scrubbing. Your team reviews the flags and handles the exceptions. The routine work runs in the background.
That is where consistent, measurable improvement in first-pass denial rates comes from.
→ For a full comparison of what to look for when choosing a platform, read our guide on choosing the best AI denial management solution with all key criteria.
Start with the two or three denial reasons that cost you the most
The top denial reasons in this guide have not changed in years. What changes is whether your team has a workflow built to catch them.
Fixing two or three of the biggest categories will have more impact on your revenue cycle than almost anything else you can do this quarter. Start with your highest-volume denial reason, trace it to the workflow gap causing it, and fix that gap first.
If you want to see how a claim denials and solutions platform can support that work, book a free demo with Aegis Health. We'll be happy to walk you through how it fits into your existing setup.