Claim Denials: 7 Practical Fixes for Medical Practices

Claim denials split into two groups, and which group a denial belongs to decides how you fix it. Most are preventable before the claim ever leaves your office, caused by eligibility, authorization, documentation or coding gaps that were knowable at the front desk. The rest are payer decisions you have to work after the fact, through a corrected claim or a formal appeal. Practices that hold their denial rate under 5 percent are rarely better at arguing with payers. They are better at the unglamorous front end work that keeps claims out of the denial pile to begin with.

The second difference is that they actually work the list, on a schedule, every week. Claim denials left sitting for two months are usually claim denials you lose, because appeal windows are shorter than most people expect and the filing clock never pauses while a claim waits in a queue. The seven fixes below run in the order they pay off, and they come from two places: the billing operation inside the clinic our team runs, and the federal rules that set the deadlines you are working against.

What is the difference between a rejection and a claim denial?

A rejection never reached adjudication. A denial did. That distinction matters because rejected claims are invisible in most denial reporting, and a claim that quietly failed a format check at the clearinghouse can sit unnoticed until it is too old to file. Counting only what a payer formally denied will understate the problem.

Fix 1: check acceptance at all three layers, not just the last one. Every claim passes three checkpoints, and each one produces its own report: your practice management system’s internal validation, the clearinghouse acknowledgement or rejection, and the payer’s own acknowledgement or rejection. In our clinic the rule is that all three report types get reviewed daily, within 24 hours, and that the team reads the acceptance reports rather than only the rejection reports. The reasoning is worth stealing: an acceptance report is the only proof a claim actually reached the payer. Without it, claims can go missing and simply never get paid, and nothing in your aging report will tell you, because a claim that never arrived never becomes one of your claim denials.

Why do claims get denied?

Almost every denial you will see sorts into eight buckets. Sorting matters more than it sounds, because the bucket determines the action, and guessing at the action is how practices burn staff hours on claim denials that were never appealable in the first place.

Fix 2: route claim denials by bucket instead of handling them one at a time. These are the categories our billing team routes against, with the action attached to each.

Whatever bucket it lands in, the last step is the same and it is the one most often skipped: write down the denial reason, the action taken, the date, and the follow up plan, on the claim itself. Claim denials worked from memory are claim denials that get worked twice.

How do you tell a real denial from a contractual adjustment?

This is where most denial reports go wrong, and it is the single highest leverage item in this article. A remittance line can show zero paid for reasons that have nothing to do with a denial, and if your worklist does not separate them, your team spends its week on lines that were never collectible.

The codes on a remittance are Claim Adjustment Reason Codes, maintained by X12, and they describe why a line was paid differently than it was billed. Two of them are routinely mistaken for claim denials. Code 45 is a charge exceeding the fee schedule or contracted amount, which is your contractual write down, not a denial. Code 253 is the sequestration reduction in federal payment, which is also not a denial. Patient responsibility lines are a third category, and they belong to your patient balance process rather than your appeal queue.

Fix 3: pick the primary actionable code on every line before you build a worklist. When a line carries several codes, our reconciliation skips the patient responsibility codes, skips 45, skips 253, and skips the remark codes, then takes the first code left standing. That surviving code is what the line is really about. The reverse trap costs just as much: if a line shows zero paid alongside a genuine denial code, it was still denied, merely priced. Missing authorization, missing information and bundling claim denials all show up this way, and they are entirely workable. Judging a line by whether money moved will hide them.

What should happen before a claim ever goes out?

Front end prevention is cheaper than any appeal you will ever write. Four controls do most of the work.

Fix 4: put hard gates in front of the claim rather than soft reminders. In our clinic, eligibility is verified the same day as the initial consultation with no exceptions, and it checks four things rather than one: that coverage is active, whether the provider is in network, whether the plan requires a referral, and whether the service requires prior authorization. Appointments for referral required services cannot be confirmed without a valid referral in the system. Benefits get re-checked the day before the visit, and if the patient is not eligible or the authorization is not approved, the appointment is rescheduled rather than seen and billed on hope. The full pre-visit routine, including what the payer’s response has to contain before an appointment counts as cleared, is in our guide to insurance eligibility verification.

The gate that surprises people is the documentation one. Charges are not reviewed against an unsigned note, ever. An unsigned note can still be edited, so charges reviewed against one may not match what the record eventually says, and that gap is exactly what a payer finds later. Charge entry happens the same day, notes are signed by the end of the service week, and claims go out within 24 to 48 hours of the date of service. That pace is not about tidiness. Getting charges out same day is what makes next day authorization work possible and what keeps claims clear of untimely filing denials.

Authorization deserves its own discipline, since it drives a large share of avoidable claim denials. Requests go in within 24 hours of the consult, the tracker is reviewed every morning, and anything pending beyond 10 days gets chased rather than waited on. Our full walkthrough of that workflow is in the guide to the prior authorization process. Enrollment problems cause the same class of avoidable claim denials, which is why credentialing in medical billing belongs in the same conversation: a provider who is not yet loaded with the payer will generate denials no biller can appeal away.

It is worth knowing how often authorization decisions go against you and what happens when they are challenged. KFF’s analysis of CMS data found that Medicare Advantage insurers fully or partially denied 7.7 percent of prior authorization requests in 2024, that only 11.5 percent of those denials were appealed, and that 80.7 percent of the appeals were partially or fully overturned. Those figures cover prior authorization decisions in Medicare Advantage rather than post service claim denials, so do not read them as a general denial rate. Read them as a comment on appealing: the challenge is rarely made, and when it is made it usually succeeds.

How long should you wait before chasing a claim?

Waiting is not free, and most practices wait too long because nobody ever set a threshold. Ours is written down and, more usefully, configured inside the practice management system so the software surfaces the list instead of relying on somebody to remember.

Fix 5: check the portal before you touch the claim. The no response protocol starts by looking, not sending. If the portal shows the claim was paid, the remittance simply never arrived electronically and you post it manually. If it shows denied, you post the denial and work it. If it shows pending adjudication, there is nothing for you to do and you recheck in two weeks. If records were requested, you send them. If there is no record of the claim at all, that is when you call.

The rule underneath all of that is one line long and saves an enormous amount of rework: do not blindly resubmit old claims. If the payer already adjudicated it, a resubmission generates a duplicate denial, which is code 18 on the remittance, and now you have two problems instead of one. When a claim genuinely is stuck on the payer’s side, ask the payer to reprocess it on their end, then record the date, the representative’s name and the reference number.

How should a practice work its claim denials worklist?

Order of work is a real lever. Our list of claim denials sorts by allowed amount ascending, so lines with zero allowed come first. Those are full claim denials and they tend to be the cleanest appeals, with a single clear reason to answer. Lines with an allowed amount above zero are priced or partial claim denials, which are still workable but usually need a modifier correction or additional records rather than an argument.

Fix 6: send the right kind of resubmission. There are three paths, and picking the wrong one restarts the clock for nothing. A simple rebuild is right when the claim went to the wrong payer, or when the payer does not accept corrected claims at all. A true corrected claim needs the correct submission reason code plus the original claim control number pulled from the first remittance, so keep that remittance. The third case catches people out: when part of the claim paid and part denied, the corrected lines and the already settled lines have to go back together on the same claim for the payer to adjudicate it properly.

One more habit that compounds. When a code appears that nobody recognizes, it goes on the tracker, gets resolved at the weekly review, and then gets added to a shared reference so the answer is reusable. Denial codes repeat. Solving the same one three times is a choice.

How do you appeal a denied claim, and when should you stop?

Know your deadlines before you write anything. For Medicare, 42 CFR 424.44 requires the claim itself to be filed no later than one calendar year after the date of service. Once a claim is denied, the first appeal level is a redetermination by the Medicare Administrative Contractor, and 42 CFR 405.942 gives you 120 calendar days from the date you receive the initial determination notice. Receipt is presumed to be five calendar days after the date on the notice, so the practical window is slightly shorter than the calendar suggests. A second level reconsideration by a Qualified Independent Contractor must be filed within 180 calendar days of receiving the redetermination, under the same five day presumption.

Commercial deadlines are a different exercise, and this is the part worth doing properly. We rebuilt our filing and appeal deadline table from the signed payer contracts themselves rather than from published standards, and found that several contracts say nothing at all about the appeal deadline and defer to a provider manual that was never supplied with the agreement. If you have not read yours, you do not actually know your windows. That is a conversation to have while negotiating payer contracts, not after a denial lands.

Fix 7: build the packet once, and know your stopping rule. A complete appeal carries the original claim, the denial letter or remittance showing the code, a cover letter, the relevant records and chart notes, the authorization approval where one exists, a letter of medical necessity from the provider, the payer’s own coverage policy showing the service should be covered, and proof of timely filing when that is the issue.

Knowing when to stop matters just as much. We stop when the denial reason is valid and cannot be overcome, when staff time is worth more than the balance, when multiple levels have affirmed with consistent reasoning, or when the payer’s policy plainly excludes the service. There is also one standing exception in our clinic: a denial for missing precertification or authorization, code 197, gets written off rather than appealed, because winning it can invite a recoupment review later. Your contracts may justify a different call, but make it deliberately rather than by reflex.

Be careful which denial statistics you plan around

One number turns up in nearly every article written about claim denials: that up to 65 percent of denied claims are never resubmitted. It appears in a widely read piece published by the Healthcare Financial Management Association, and if you follow that article’s own footnote, the figure is attributed to a vendor blog post from June 2018, not to a study with a disclosed sample or method. The article itself dates from 2018.

That does not make the number wrong. It does mean it is not evidence, and it is certainly not a benchmark for your practice. The same caution applies to the familiar cost per reworked claim figures floating around trade publications, most of which trace back more than a decade. Measure your own claim denials rate and your own rework volume for one quarter. Your numbers will be more useful than anybody’s industry average, and they will be about your payer mix rather than a hospital system’s.

What should you measure?

Four numbers tell you whether any of this is working. Denial rate under 5 percent. First pass clean claim rate above 95 percent. Days in accounts receivable under 35. And the one nobody tracks: claims sitting 30 days or more with no payer response should be zero unworked, not merely visible on a report. These sit inside the broader set of medical practice KPIs worth reviewing on a fixed rhythm.

Cadence beats intensity here. Claim denials get worked daily, not in a monthly cleanup. A weekly review with the practice manager closes out anything complex and catches the codes nobody recognized.

When is it worth bringing in outside help?

If your denial rate sits above 10 percent, if nobody can tell you today how many claims are more than 30 days old with no payer response, or if your team is reworking the same denial reason every month, the problem is usually process rather than effort. That is fixable in place, and it does not require handing your billing to somebody else. If you are weighing that decision anyway, our guide on when to outsource medical billing lays out the questions to answer first.

Practice Management Consultancy advises independent practices on exactly this: reading your own contracts, setting the thresholds, building the worklist, and training the people who work it. We are consultants rather than a billing vendor, and our team runs this operation daily inside its own clinic. If you want a second pair of eyes on why your claim denials keep repeating, get in touch or call (706) 909-3271.

Frequently asked questions about claim denials

What is a good claim denial rate for a medical practice?

Under 5 percent is the working target, and strong performers hold it lower. Above 10 percent points to a process problem rather than bad luck, usually in eligibility checks at the front desk, coding, or claim follow up. Measure it as the share of claims denied on first submission, and watch the trend rather than a single month.

How long do you have to appeal a denied Medicare claim?

A redetermination, which is the first appeal level, must be filed within 120 calendar days of receiving the initial determination notice, per 42 CFR 405.942. Receipt is presumed to be five calendar days after the date on the notice. A second level reconsideration must be filed within 180 calendar days of receiving the redetermination decision.

Is a zero paid line always one of your claim denials?

No, and treating it that way wastes real staff time. A line can show zero paid because of a contractual adjustment, code 45, or a sequestration reduction, code 253, neither of which is a denial. A line can also show zero paid alongside a genuine denial code, which means it was denied but priced, and that one is workable. Read the reason codes rather than the payment amount.

Should you resubmit a claim the payer has not responded to?

Check the payer portal first. If the claim was already adjudicated, resubmitting creates a duplicate claim denial, code 18, and adds work instead of removing it. If the portal shows the claim pending with no progress, or shows no record of it at all, call the payer and ask them to reprocess it on their end, then document the reference number.

Which claim denials are not worth appealing?

Stop when the denial reason is valid and cannot be overcome, when the staff time costs more than the balance, when multiple appeal levels have affirmed the same reasoning, or when the payer’s published policy excludes the service outright. Practices should also decide in advance how they will handle missing authorization claim denials, since a successful appeal on one can invite a recoupment review afterward.

Disclosure: our team operates and manages the medical practice referenced in first-person examples on this site.