Upcoding is when a healthcare provider or insurance plan submits billing codes for more expensive diagnoses or procedures than what was actually provided or documented. It inflates what insurers pay out, and it’s one of the most common forms of healthcare fraud in the United States. Whether it happens through careless documentation or deliberate manipulation, the result is the same: someone gets paid more than the care warrants.
How Upcoding Works
Every medical visit, test, and procedure gets translated into a standardized billing code before a claim is sent to an insurer. These codes exist on a spectrum of complexity. A quick, straightforward office visit has a lower-paying code than a comprehensive evaluation involving complex decision-making. Upcoding means selecting a code higher on that spectrum than the visit actually justified.
A common example involves emergency department visits. Billing codes for ER care range from level one (a simple, problem-focused visit) to level five (a comprehensive evaluation requiring complex medical decision-making). Level five codes reimburse significantly more than level one. Data shows that hospitals have steadily shifted their billing toward higher-level codes over time: usage of the lowest-complexity ER code rose only slightly between 2006 and 2012, while the highest-level code became far more commonly used, not necessarily because patients were sicker, but because it paid better.
Another well-documented pattern involves billing returning patients as if they were new. Medicare pays higher rates for new-patient evaluations than for established-patient follow-ups. Some providers reclassify returning patients under new-patient codes to capture that higher reimbursement, something CMS has flagged repeatedly.
Upcoding in Hospitals
Hospital billing adds another layer of complexity. When you’re admitted, your stay gets assigned a payment group based on your diagnosis and any complicating conditions. The more severe or complicated the case appears on paper, the higher the payment. Auditors look for four specific manipulation tactics in hospital billing: selecting a diagnosis group with a higher payment weight than the medical record supports, adding complicating conditions that aren’t actually present or adequately documented, coding conditions as existing before admission when they developed afterward, and breaking apart bundled services into separate charges to inflate the total bill. That last tactic, called unbundling, is technically a distinct form of fraud, but regulators treat it as a subset of upcoding because the goal is the same.
The Medicare Advantage Problem
Upcoding takes on a different shape in Medicare Advantage, the private insurance alternative to traditional Medicare. Under traditional Medicare, doctors get paid per service, so the incentive is to do more. Under Medicare Advantage, insurance companies receive a fixed monthly payment per enrollee from the government, and that payment is adjusted based on how sick the patient appears. More diagnoses on file means a higher “risk score,” which means a bigger check from the government each month.
This creates a powerful incentive to make patients look sicker on paper. Research published in the Journal of Political Economy found that people enrolled in Medicare Advantage plans generate risk scores 6% to 16% higher than they would under traditional Medicare, where diagnoses don’t directly affect payment. Across a county, moving from zero to full Medicare Advantage enrollment raises the average risk score by about 7%, roughly one standard deviation. That gap represents billions of dollars in inflated payments nationwide.
The methods insurers use to boost risk scores are varied and sometimes invisible to patients and even their doctors. Insurance companies can structure contracts with physician groups so that the group’s payment depends on the risk-adjusted amount the insurer receives from the government, directly passing the coding incentive down to doctors. After a claim is submitted, the insurer or a contractor may perform chart reviews, combing through physician notes to add diagnosis codes the original doctor never submitted. These additions are reported to the government without the physician or patient necessarily knowing. Some plans proactively contact enrollees who likely have conditions worth coding and send a nurse or doctor to their home for the sole purpose of documenting those diagnoses for the current plan year.
What It Costs the System
Healthcare fraud remains the leading source of recoveries under the federal False Claims Act, and upcoding cases, particularly in Medicare Advantage, have become a major enforcement priority. Recent settlements give a sense of the scale. Independent Health Association paid up to $98 million to resolve allegations that a subsidiary retrospectively searched medical records and contacted physicians to add unsupported diagnoses for Medicare Advantage enrollees. Seoul Medical Group and its subsidiary paid over $60 million for allegedly submitting false diagnosis codes for spinal conditions patients didn’t have, and a radiology group that helped create fake supporting reports paid an additional $2.35 million.
The Department of Justice is also actively litigating against some of the largest insurers in the country. Cases against UnitedHealthCare, Kaiser, and Anthem allege that these companies systematically added improper diagnoses to increase their Medicare Advantage reimbursements. These aren’t fringe operators. They’re among the biggest names in American health insurance.
How Upcoding Gets Caught
Auditors flag upcoding by looking for statistical patterns that don’t match clinical reality. A practice that bills nearly every visit at the highest complexity level, or a hospital whose patients consistently appear far sicker than the regional average, will attract scrutiny. The core question is always whether the documentation in the medical record actually supports the code that was billed.
For hospitals, auditors examine whether the base diagnosis group was appropriate, whether any complicating conditions listed in the claim are actually documented in the chart, whether conditions were honestly classified as pre-existing, and whether bundled services were improperly separated. For Medicare Advantage plans, the government compares the diagnosis patterns of enrollees before and after they switch from traditional Medicare, looking for suspiciously rapid increases in documented conditions.
How It Affects Patients
Upcoding doesn’t just cost the government money. It can directly affect you. If a provider bills your visit at a higher complexity than what actually happened, your copay or coinsurance may be higher. Your medical record may reflect conditions you don’t actually have, which can influence future care decisions, insurance coverage, or even life insurance applications. In the Medicare Advantage context, inflated risk scores drive up the overall cost of the program, which ultimately comes from taxpayer funding.
If you receive an Explanation of Benefits from your insurer and notice charges for services you don’t recognize or complexity levels that seem inflated compared to what actually happened during your visit, that discrepancy is worth questioning. You can contact your provider’s billing department directly or report concerns to the Office of Inspector General’s fraud hotline.