Can AI Draft an Appeal Letter for a Medical Insurance Denial?

Insurers already deny with software

The pattern is documented. In March 2023, ProPublica reported that Cigna ran an internal system it called PXDX that flagged claims when a procedure did not match an approved diagnosis list. Using that system, Cigna doctors denied roughly 300,000 claims over a two-month stretch, spending an average of about 1.2 seconds on each, according to internal records reviewed by ProPublica. Class-action suits followed, and a federal court in California allowed parts of one case to move forward. Cigna disputes the claims.

A parallel story involves UnitedHealth. In November 2023, STAT News reported on a lawsuit over an algorithm called nH Predict, built by naviHealth, that estimated how long Medicare Advantage patients should stay in rehab or skilled-nursing care. The suit alleges the company used the tool to cut coverage early. UnitedHealth says the tool only guides care planning and that coverage decisions follow Medicare rules. The allegations are contested in court, but they reflect a real shift: decisions about your care are increasingly shaped by code.

Most denials are never challenged

Denials are common, and appeals are rare. KFF found that HealthCare.gov insurers denied about 20%, or one in five, of in-network claims in 2023. Out of roughly 86 million denied in-network claims, consumers appealed only 376,508, an appeal rate under 1%. That gap is the whole problem. Insurers can deny in bulk because they know almost no one fights back.

Appealing works more often than people expect

When patients do appeal, outcomes change. KFF found that about 44% of appealed in-network marketplace denials in 2023 were overturned in the consumer's favor. Our analysis of 73,987 real external-review outcomes points the same direction: 46.9% of appealed denials were overturned. A denial letter is a first answer, not the final word.

Where AI genuinely helps

A strong appeal takes work most people do not have time for. You have to read the denial, find the exact reason, match it against your plan's language and the rules that apply, and assemble the clinical evidence into a clear argument. That is precisely the kind of structured drafting AI does well and quickly. It turns a blank page into a complete, organized appeal in minutes.

It is not magic, and we will not pretend otherwise. AI drafts the argument; a human reviews the facts and the medical record before anything goes out, and no tool can promise a specific result. What it can do is remove the main reason most people never appeal: the effort. If software helped deny your claim, it is reasonable to use software to help you answer.

Frequently asked questions

Can AI really write a medical insurance appeal letter?

Yes. AI can read your denial, identify the stated reason, line it up against your plan terms and the applicable regulations, and assemble the clinical and policy argument into a complete draft. A person should review it before you send it, and no tool can guarantee approval.

Is it worth appealing a denial at all?

Often, yes. KFF found roughly 44% of appealed in-network marketplace denials in 2023 were overturned, and our analysis of 73,987 external-review outcomes shows 46.9% overturned. Yet KFF found consumers appeal fewer than 1% of denials.

Do insurers really use algorithms to deny claims?

Reporting and litigation say they do. ProPublica documented Cigna's PXDX system denying about 300,000 claims in two months, and STAT News reported on a lawsuit over UnitedHealth's nH Predict tool. Some specifics are alleged and contested in court, but automated review is well established.