Health Insurance Lawyer: Fight a Denied Claim in 2026

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Your doctor says the treatment is necessary. The surgery is scheduled. Then the letter arrives: denied.

By the time you open that envelope, you have already lost time — and time is the one thing a denied health insurance claim cannot spare. Here is what most people miss: the majority of claim losses have nothing to do with whether the denial was clinically correct. They happen because someone missed a filing window, relied on the wrong version of their plan document, or assumed their employer plan worked the same way as the individual policy their neighbor buys on the marketplace.

Let me be direct: you do not need to become an expert in insurance law today. You need to answer three questions. Is your plan governed by ERISA appeal rules or by state insurance law? What is your exact filing deadline? And is a health insurance lawyer worth the cost for what you are actually trying to recover?

I spent twelve years on the insurer’s side of the table, handling contested claims across multiple jurisdictions. I have watched policyholders win cases they expected to lose — and lose cases they should have won — on procedure alone. This article walks through the machinery in the order it will hit you: plan type, denial type, appeal ladder, bad faith, cost, and what changed in 2026.

What a Health Insurance Lawyer Actually Does

A health insurance lawyer reviews your denial letter against your plan document, confirms the appeal deadline, builds the medical-necessity record with your treating physician, and drafts and files the internal appeal, external review, or lawsuit. Under ERISA, remedies are usually limited to the denied benefit plus discretionary attorney fees under 29 U.S.C. § 1132(g).

That paragraph is the answer. Everything below is the detail the answer compresses — and the detail is where cases are won or quietly lost.

The four tasks every case starts with

When a health insurance claim denial lawyer opens a new file, the first week looks almost identical across firms. Four tasks run in parallel.

• Read the denial letter against the plan text. The denial cites a reason — medical necessity, an exclusion, an eligibility technicality. The lawyer checks whether that reason maps to language actually present in the governing plan document.
• Map the deadline. Every denial letter should state the appeal window. Under the ERISA claims procedure regulation, group health plans must give a claimant generally at least 180 days after receipt of an adverse benefit determination to appeal. State-regulated plans can differ.
• Build the clinical record. This is the task clients underestimate. The treating physician’s letter, the peer-reviewed literature, the clinical guidelines, and the patient’s functional history all become the spine of the appeal.
• Draft the appeal or the complaint. Under ERISA, litigation is anchored in § 502(a)(1)(B), which lets a participant sue “to recover benefits due to him under the terms of his plan.”

Notice what is not on that list: calling the insurer to negotiate. In my experience, the phone call is where policyholders burn the clock. Nothing said on a recorded service line changes the record the reviewer will actually read.

What a lawyer cannot change about your policy

Here is the part the marketing pages skip. A lawyer cannot make an excluded service covered. If the plan document explicitly excludes a treatment category and the exclusion is lawful and clearly drafted, no appeal strategy overcomes it. A lawyer also cannot obtain treatment faster — external review takes months, litigation takes longer. Anyone promising urgency is selling something else.

What counsel can change is the quality of the record, the accuracy of the deadline calculation, and the willingness of the insurer’s counsel to settle rather than litigate. To put it plainly: good representation shifts the cost-benefit math on the other side of the table.

How a health insurance lawyer differs from a personal injury attorney

These are different disciplines and the confusion costs people cases. A personal injury attorney pursues a third party who caused harm — a driver, a manufacturer, a property owner. A health benefits attorney pursues a contractual obligation under an insurance plan or an ERISA welfare benefit plan.

The overlap is narrow. Some accident cases involve both a liability claim and a health coverage dispute over who pays first. But the statutes, the deadlines, and the courts are different. If a firm advertises “injury and insurance” without a health benefits practice, ask directly how many ERISA benefit denials they have litigated. Firms such as Kantor & Kantor, which reports 20-plus years focused on appealing and litigating insurance denials nationwide (2026), are the exception rather than the rule.

• Denial letter — with the date of receipt documented
• Plan document or summary plan description (SPD) — the controlling text
• Medical records — clinical notes, imaging, test results, treatment history
• Treating physician support letter — stating medical necessity in the plan’s own vocabulary
• Appeal history — every letter, fax confirmation, and portal submission

Now that the role is defined, the next question is more important than the lawyer question itself: which legal regime governs your plan? That determines everything that follows.

ERISA vs. Fully Insured Plans: Which Rules Apply to You

This is the single most misunderstood distinction in American health coverage — and no ranking page explains it properly. The answer changes your deadline, your forum, the evidence that matters, and the damages available to you.

The test is not what your employer calls the plan. The test is who pays the claims.

If your employer pays claims from its own general assets, the plan is self-funded and governed by the Employee Retirement Income Security Act (ERISA). ERISA preempts state insurance law — including state bad-faith statutes. If your employer bought a policy from a carrier and the carrier pays the claims, the plan is fully insured, and state insurance codes apply alongside ERISA’s procedural rules.

I have seen this go wrong too many times. A policyholder in a self-funded plan reads a state bad-faith statute online, assumes it applies, and signs a fee agreement with a lawyer who has never litigated under ERISA. Six months later the case is dismissed on preemption grounds. The claim had merit. The theory did not.

Three questions that identify your plan type

• Does your insurance card carry the name of a major carrier, or your employer’s own name? A carrier-branded card points toward fully insured; an employer-branded administrative arrangement points toward self-funded.
• Does your plan document contain language about “plan assets” or a trust? Self-funded plans frequently reference a trust or a plan sponsor’s obligation to pay benefits from general assets.
• Does your SPD reference state insurance department jurisdiction or external review under state law? Fully insured plans generally do; self-funded ERISA plans route external review through federal standards instead.

None of these three questions is conclusive on its own. Together, they usually settle it. And if you still are not certain, the answer is in the plan document or the SPD — not in a customer service script.

How to read your summary plan description (SPD)

The SPD is the plain-language summary of the plan document that ERISA requires plan administrators to furnish. It must describe eligibility, benefits, claim procedures, and the participant’s rights. In practice, the SPD is usually what you will cite in an appeal, because it is the document the plan itself gives you.

Read it in this order: the claims procedure section, the exclusions section, and the definitions section. The claims procedure tells you the deadline. The exclusions tell you what the denial is likely built on. The definitions tell you what the plan means by “medical necessity” — which is almost never the same as what your doctor means.

Request the full plan document separately. The SPD controls only where it does not conflict with the plan.

	Self-Funded ERISA Plan	Fully Insured Plan
Governing law	ERISA, federal	ERISA procedures plus state insurance code
Internal appeal deadline	Generally at least 180 days from adverse determination	Generally at least 180 days; state rules may extend or add requirements
External review	Federal ERISA external review standards	State external review plus federal minimums
Who you sue	The plan and the plan administrator	The carrier
Damages available	Plan benefit plus discretionary attorney fees	Plan benefit, potentially extra-contractual and bad-faith damages
Bad-faith exposure	Preempted	Available under state law in most states

Why the distinction changes your damages

Under ERISA, a prevailing claimant can recover the value of the benefit that was wrongly denied. A court may, in its discretion, also award reasonable attorney fees under 29 U.S.C. § 1132(g). That is the ceiling for most ERISA cases.

Under state insurance law, depending on the jurisdiction, a claimant may recover the denied benefit, consequential damages, and in some states statutory penalties or extra-contractual damages where the insurer’s conduct met the bad-faith standard. The difference can be an order of magnitude.

That is why an ERISA appeal attorney asks about plan funding in the first five minutes. The legal theory follows the funding source. Once you know your track, the next variable is what kind of denial you are actually fighting.

The Five Denial Types and How Each Is Fought

Treating “denial” as one category is the most common analytical error on the policyholder side. The evidence that wins a medical necessity dispute is irrelevant to an eligibility error. A medical necessity denial attorney builds a clinical record; an eligibility case turns on enrollment documents and premium receipts.

Segment first. Then build.

Medical necessity denials

The insurer’s utilization review team applies criteria — often licensed from a third-party vendor — and concludes the service does not meet the plan’s definition of medical necessity. Your doctor disagrees. Both can be “right” in their own framework, because they are answering different questions. Your doctor asks whether the treatment will help you. The plan asks whether it meets the plan’s stated criteria.

The winning move is to make those two questions converge. That means a treating-physician letter that maps the clinical facts onto the plan’s own criteria language, plus the applicable specialty society guideline and any peer-reviewed literature supporting the treatment.

Experimental and investigational exclusions

These denials assert that the requested service falls outside coverage because it lacks sufficient evidence of effectiveness. They are frequently reversible — because “insufficient evidence” is a factual claim that can be rebutted with published data.

What wins: peer-reviewed studies, national coverage determinations, specialty society recommendations, and FDA labeling or clearance. What loses: a letter from your doctor saying “I believe this is necessary” with no supporting literature. In this category, the physician’s opinion is the framing — the evidence is the argument.

Prior authorization and retroactive denials

Prior authorization and retroactive denials

Two distinct problems sit under this heading. The first is a prior authorization denial — you sought approval in advance and were refused before treatment. The second is a retroactive denial, where a service was already delivered under an authorization and the insurer later reverses itself.

Retroactive rescissions face meaningful legal constraints. If the authorization was issued and you relied on it, the plan’s ability to reverse coverage after the fact is limited. Document the authorization number, the date, the representative’s name, and any written confirmation. In these cases the paper trail is the case.

Out-of-network and balance billing disputes

Here the dispute is often not with your insurer at all, but with a provider billing above the allowed amount, or with an insurer paying an out-of-network claim at a rate far below the billed charge. Since 2022 the No Surprises Act has reshaped part of this landscape and created an independent dispute resolution process for certain payment disputes — a topic covered in detail further down.

Administrative and eligibility errors

Wrong member ID. A coverage termination processed one cycle early. A COBRA election not credited. A dependent flagged as ineligible after a status change. These denials are the most fixable and the most frustrating, because they have nothing to do with medicine. They are resolved with enrollment records, payroll deductions, and premium payment confirmations — not clinical evidence.

Denial Type	Evidence That Usually Wins	Typical Resolution Timeline
Medical necessity	Treating-physician letter mapped to plan criteria, specialty guidelines	30–60 days at internal appeal
Experimental / investigational	Peer-reviewed literature, society recommendations, FDA status	45–90 days, often resolved at external review
Prior authorization / retroactive	Authorization number, written confirmation, dates of reliance	30–45 days
Out-of-network / balance billing	Billing records, allowed-amount documentation, NSA eligibility	Varies; NSA IDR can run several months
Administrative / eligibility	Enrollment records, payroll deductions, premium receipts	Often 2–4 weeks

Consider a case that came across my desk years ago. A policyholder’s long-term care claim was denied on the ground that the care was “custodial” rather than “medically necessary.” Those two words were doing enormous work. The plan defined medically necessary care as care requiring the skills of licensed nursing personnel. The denial letter asserted the care was custodial.

We rebuilt the file around the daily skilled nursing interventions documented in the facility notes — wound care, medication titration, monitoring for a condition with known instability. Once those entries were mapped onto the plan’s own definition, the plan’s reviewer conceded the care was not custodial. The denial reversed on internal appeal, before any litigation was filed. The claim had been denied for eight months. The reclassification took three weeks.

Knowing the denial type tells you what evidence to gather. Knowing the process tells you where to send it — and by when.

The Appeal Ladder: Internal Review, External Review, and Court

There are three rungs, and you climb them in order. Skipping a rung generally means starting over — or losing the claim.

Step 1: The internal appeal and the record you build

The internal appeal is a request that the plan reconsider its adverse benefit determination. Under the ERISA claims procedure regulation, a claimant generally has at least 180 days following receipt of the adverse determination to file. The plan document controls and may be more generous, rarely less.

The internal appeal is not a negotiation. It is the construction of an administrative record that a court may later review under a deferential standard. Every document you submit here becomes part of that record. Every document you omit may not be admissible later.

If I were filing this claim myself, I would submit three things: the treating physician’s letter, the supporting clinical literature, and a short cover document that walks the reviewer through the plan’s own criteria point by point. Reviewers read dozens of files a week. Make yours easy to approve.

Group health plans must generally decide pre-service appeals within 30 days and post-service appeals within 60 days, with extensions permitted in limited circumstances.

Step 2: External review before an IRO

If the internal appeal is denied, most ACA-compliant plans must offer external review before an independent review organization (IRO) — an entity with no financial stake in the outcome, staffed by clinical reviewers in the relevant specialty. External review generally must be requested within four months of the final internal denial, though the plan document and state rules control.

The IRO does not start from scratch. It reviews the record you built. That is why legal input is most valuable before the first appeal, not after it fails. A strong IRO case is a strong internal appeal, refiled in front of a different reader.

For self-funded ERISA plans, external review runs under federal standards rather than the state process — but the underlying logic is the same: an independent clinical reviewer decides whether the denial meets the plan’s criteria.

Step 3: Litigation and what a court can order

If external review fails, the path depends on your plan type. ERISA claimants must generally exhaust the plan’s internal appeal process before filing suit, and the suit is brought under § 502(a)(1)(B) to recover benefits due under the plan. A court can order the plan to pay the benefit, and may award attorney fees under § 1132(g) in its discretion.

Fully insured claimants may file state-law claims, including bad faith, in addition to or instead of ERISA claims depending on the posture. Remedies there can include the denied benefit, consequential damages, and in some jurisdictions statutory penalties.

Timing matters in litigation too. Under 29 U.S.C. § 1132(a)(1)(B), the claim accrues on final denial. Many courts apply the most analogous state statute of limitations — often the four-month window used for certain benefit claims — unless the plan itself specifies a contractual limitations period, which many do. If you are past external review, the clock is already running.

Stage	Who Decides	Typical Filing Window	What You Must Submit
Internal appeal	Plan administrator or carrier appeal unit	Generally at least 180 days from adverse determination — confirm against your plan document	Treating-physician letter, clinical records, plan-criteria argument
External review	Independent review organization (IRO)	Generally within four months of final internal denial — timelines vary	Complete appeal record, IRO request form, supporting literature
Litigation	Federal or state court	Controlled by plan limitations period or analogous state statute — verify with counsel	Full administrative record, complaint, exhaustion evidence

A denial that arrives on time and loses on the merits is one problem. A denial that becomes a bad-faith claim is a different one — and a more serious one for the insurer.

When a Denial Becomes Bad Faith

Insurers deny claims for legitimate reasons every day. Sometimes the treatment truly is outside the plan’s definition. Sometimes the service genuinely lacks peer-reviewed support. A denial is not evidence of wrongdoing. What matters is the process the insurer used to reach it.

Four behaviors that support a bad-faith claim

• Unreasonable investigation. Denying without requesting records, without reviewing the treating physician’s rationale, or without any clinical review by a qualified professional.
• Ignoring the treating physician. Relying on a reviewing doctor who never examined the patient and who contradicts the treating specialist without explanation.
• Misrepresenting the policy. Citing an exclusion that does not exist in the plan document or paraphrasing a definition in a way that changes its meaning.
• Applying criteria outside the plan. Using internal utilization-review guidelines that are stricter than the plan’s stated definition of medical necessity.

Why ERISA blocks punitive damages

ERISA’s remedies are equitable in nature. Courts have repeatedly held that § 502(a)(1)(B) does not authorize compensatory or punitive damages beyond the plan benefit. A claimant who suffered real harm from a wrongful denial recovers the benefit — not the harm the delay caused.

This is why the fee-shifting provision under § 1132(g) matters so much. If the benefit itself is the ceiling, the only way litigation becomes rational for a mid-sized claim is if attorney fees are recoverable. A court’s discretionary fee award can be the difference between a winnable claim and an economically impossible one.

Where bad-faith claims are strongest

Bad-faith exposure is a creature of state law, so the answer is jurisdictional. Generally speaking, states with established insurance bad-faith jurisprudence and statutory penalties provide the strongest footing for a fully insured policyholder. State insurance departments track complaints as well; a documented pattern of complaints against the same carrier in the same state can support the unreasonable-conduct element.

I should be clear about a limit: this framework applies to fully insured plans. If your plan is self-funded, the bad-faith analysis is largely academic — the claim goes through ERISA or it does not go at all.

The cost question now becomes unavoidable. If the damages are limited to the benefit, is hiring counsel economically rational?

What It Costs and How Lawyers Get Paid

This is the question searchers ask most and find answered least. Here is the honest version.

Contingency, hourly, and flat-fee appeals

Three fee models dominate health benefits work, and the right one depends on the case posture. Contingency arrangements align the lawyer’s interest with recovery but only work where the potential benefit is large enough to justify the risk. Hourly billing gives the client control but exposes them to cost uncertainty. Flat-fee appeals are increasingly common for the internal and external review stages, because the work is bounded.

Fee-shifting under ERISA section 502(g)

Under 29 U.S.C. § 1132(g), a court has discretion to award reasonable attorney fees to a prevailing party in an ERISA action. This is the mechanism that makes smaller claims viable. A claim that would not justify a $15,000 contingency fee may justify a $4,000 internal appeal when the client knows that a fee award is recoverable if the case goes to court and succeeds.

Fee-shifting is discretionary, not automatic. Do not assume it applies. Ask your lawyer how often they have obtained a fee award under § 1132(g) and in which courts.

When a claim is too small to justify counsel

To be blunt: some claims are better handled alone. If the disputed amount is a few hundred dollars and the service is out-of-network, the cost of legal review can exceed the recovery. If the denial is administrative — a wrong member ID or an uncredited payment — the fix is usually a phone call and a resubmission, not a legal engagement.

The threshold question is not the dollar amount. It is whether the denial is a pattern. If the same service has been denied repeatedly, or if the insurer is applying a criterion your plan does not contain, the strategic value of counsel rises even if the immediate dollar figure is modest.

Fee Model	Typical Structure	Best Fit
Contingency	Percentage of recovered benefit, paid only on recovery	Larger denied benefits, litigation posture
Hourly	Time-based billing with retainer	Complex cases needing broad strategic input
Flat-fee appeal	Fixed sum per appeal stage	Internal or external review with bounded scope

Fee terms are always firm-specific. Confirm everything in writing before work begins.

Before you make the call, though, you should know what shifted in the regulatory landscape this year — because two 2026 changes affect how denials and out-of-network bills are handled.

2026 Update: No Surprises Act and Prior Authorization Reform

The No Surprises Act independent dispute resolution process is the piece most ranking pages still do not explain. It matters because it moved a category of disputes out of the courts and into arbitration.

What the No Surprises Act does and does not cover

The No Surprises Act, effective for plan years beginning on or after January 1, 2022, protects patients from most surprise out-of-network bills in emergency care and in certain non-emergency situations at in-network facilities. It also created an independent dispute resolution process — NSA IDR — for payment disputes between providers and insurers.

Here is the crucial limitation. NSA IDR is a provider–insurer process. It is not a patient appeal mechanism. If your claim was denied for medical necessity, the No Surprises Act does not help you. If you received a surprise out-of-network bill that the Act covers, the billing protection applies to you directly, and the payment dispute between the provider and the insurer runs through IDR without you.

Advanced Explanation of Benefits and price transparency

The Advanced Explanation of Benefits requirement is designed to give patients a good-faith estimate of costs before a scheduled service, along with information about whether the provider is in network and what prior authorization may be required. Implementation timelines have moved more than once since the statutory text was enacted, and the current effective dates require verification with counsel.

For policyholders, the practical effect is that if you receive an AEOB that conflicts with the final bill, you have documentary evidence of what you were told. Keep it. That is exactly the kind of record that supports a dispute over unexpected charges.

State prior authorization reform

State legislatures have continued to tighten prior authorization rules, and the changes tend to move in the same direction: shorter response deadlines for urgent requests, requirements that denials be made by a physician in the relevant specialty, and mandated disclosure of the specific criteria used. The coverage gap between states is real, and a fully insured policyholder in a reform-oriented state may have materially stronger procedural protections than a self-funded plan participant sitting in the same zip code.

With the regulatory picture in view, the last practical question is who to hire and how to test them in the first ten minutes.

How to Choose a Health Insurance Lawyer

Health benefits law is narrow. Many competent general litigators have never handled an ERISA benefit appeal, and the reason is structural: ERISA cases are procedurally distinct, the administrative record rules are unforgiving, and a lawyer who treats them like a standard contract dispute will lose on procedure. The Law Office of Mark P. Scherzer reports more than 55 years’ combined legal experience in health benefits law (2026) — that specificity is what you are looking for.

Five questions to ask before you hire

• How many ERISA benefit denials have you litigated in the past two years? Ask for a number and a venue. Vague answers are answers.
• Is my plan self-funded or fully insured? If the lawyer cannot answer this within the first call, they have not done the analysis.
• What is my internal appeal deadline, and what is my external review deadline? A competent practitioner will know the ERISA default and will ask to see your plan document to confirm the specifics.
• What is the fee structure, and do you pursue § 1132(g) fee awards? Get this in writing.
• Who handles the file day to day — you, a partner, or an associate? You are hiring a person, not a letterhead.

Why general litigators often miss ERISA deadlines

ERISA is a procedural minefield dressed as a benefits statute. Exhaustion is generally required before suit. The administrative record is largely closed once the appeal is decided. Discovery is limited. The standard of review may be deferential if the plan grants discretion to the administrator. These features are not intuitive, and a lawyer who assumes ordinary commercial litigation rules will miss them.

I have reviewed files where a general litigation firm filed a state-court complaint on a self-funded plan and lost months before anyone noticed the plan was ERISA-governed. The client’s claim was not weak. The firm’s procedural instincts were.

Free consultation versus free case evaluation

These sound identical and are not. A free consultation is a conversation. A free case evaluation means the firm will review your denial letter and plan document and tell you whether you have a case, usually at no charge. If a firm offers only a “free consultation” but will not read the documents before quoting a fee, you are being sold, not evaluated.

Ask for the evaluation. Send the documents. Then decide.

• Denial letter, with the date you received it recorded in writing
• Plan document or SPD, including the claims procedure and exclusions sections
• Medical records covering the treatment at issue
• Treating physician support letter addressing medical necessity
• Any appeal correspondence already exchanged, with dates
• Written list of key dates: denial received, appeal filed, appeal denied, external review filed

Frequently asked questions

How long do I have to appeal a denied health insurance claim?

ERISA group health plans generally give you at least 180 days from the adverse benefit determination to request a plan-level appeal. External review generally must be requested within four months of the final internal denial. Your plan document controls and may impose different timelines, so locate the date on your denial letter immediately.

Can I sue my health insurance company for denying a claim?

Yes, but for ERISA claims you generally must exhaust the plan’s internal appeal process first. Remedies vary sharply: ERISA typically limits recovery to the plan benefit plus discretionary attorney fees, while fully insured plans may allow state bad-faith claims with broader damages.

What is the difference between an ERISA plan and a fully insured plan?

A self-funded employer plan pays claims from company assets and is governed by ERISA, which preempts state bad-faith law. A fully insured plan uses a purchased policy, so state insurance codes and bad-faith remedies apply. A three-question diagnostic based on your card, trust language, and state-law references usually identifies which one you have.

Do I need a lawyer for an external review appeal?

No — external review is designed to be accessible without counsel. However, the record built during the internal appeal determines the outcome, so legal input is most valuable before the first appeal is filed rather than after it fails.

How much does a health insurance lawyer cost?

Fee structures vary by firm and case type: contingency, hourly, and flat-fee appeals are all common. In ERISA litigation, a court has discretion to award reasonable attorney fees to a prevailing claimant under 29 U.S.C. § 1132(g), which can make smaller claims viable. Confirm the fee agreement in writing.

What is an experimental or investigational treatment denial?

It is a denial asserting the requested service falls outside coverage because it lacks sufficient evidence of effectiveness. These denials are frequently reversible when the appeal supplies peer-reviewed literature, clinical guidelines, and a treating-physician rationale connecting the evidence to the plan’s own criteria.

Does the No Surprises Act help with a denied claim?

The No Surprises Act primarily addresses surprise out-of-network billing and uses an independent dispute resolution process for payment disputes between providers and insurers. It does not replace the plan appeal or external review process for medical necessity denials.

The one thing to do today

Everything in this article compresses into a single action. Find the date on your denial letter. Write it down. Then open your plan document — or your SPD — and locate the appeal window. Count the days between those two dates. That number, not the clinical merits, is what will decide whether your claim survives the next thirty days.

Recapping the four things that determine outcomes:

• Identify your plan type first. Self-funded ERISA or fully insured changes the law, the deadline, and the damages available.
• The appeal deadline is the case. Document the date on the denial letter and confirm the window against the plan document, not against a blog post.
• Build the medical record during the internal appeal. External review and litigation are decided largely on the record you already created.
• Fee-shifting can make a healthcare insurance claim attorney viable even for claims that do not look large — but only where the theory is right and the record supports it.

The reality is straightforward: insurers rely on policyholders not knowing which clock is running. Once you know yours, the asymmetry shifts. So — what is the date on your denial letter, and how many days do you have left?